diff --git a/src/mock.rs b/src/mock.rs
index e44351ee..30bd4a6e 100644
--- a/src/mock.rs
+++ b/src/mock.rs
@@ -1,7 +1,8 @@
 use std::cmp;
 use std::io::{self, Read, Write};
 
-use futures::Poll;
+use bytes::Buf as BufTrait;
+use futures::{Async, Poll};
 use tokio_io::{AsyncRead, AsyncWrite};
 
 #[derive(Debug)]
@@ -11,10 +12,6 @@ pub struct Buf {
 }
 
 impl Buf {
-    pub fn new() -> Buf {
-        Buf::wrap(vec![])
-    }
-
     pub fn wrap(vec: Vec<u8>) -> Buf {
         Buf {
             vec: vec,
@@ -63,23 +60,27 @@ impl Read for Buf {
     }
 }
 
+const READ_VECS_CNT: usize = 64;
+
 #[derive(Debug)]
 pub struct AsyncIo<T> {
-    inner: T,
+    blocked: bool,
     bytes_until_block: usize,
     error: Option<io::Error>,
-    blocked: bool,
     flushed: bool,
+    inner: T,
+    max_read_vecs: usize,
 }
 
 impl<T> AsyncIo<T> {
     pub fn new(inner: T, bytes: usize) -> AsyncIo<T> {
         AsyncIo {
-            inner: inner,
+            blocked: false,
             bytes_until_block: bytes,
             error: None,
             flushed: false,
-            blocked: false,
+            inner: inner,
+            max_read_vecs: READ_VECS_CNT,
         }
     }
 
@@ -90,6 +91,22 @@ impl<T> AsyncIo<T> {
     pub fn error(&mut self, err: io::Error) {
         self.error = Some(err);
     }
+
+    pub fn max_read_vecs(&mut self, cnt: usize) {
+        assert!(cnt <= READ_VECS_CNT);
+        self.max_read_vecs = cnt;
+    }
+
+    #[cfg(feature = "tokio-proto")]
+    //TODO: fix proto::conn::tests to not use tokio-proto API,
+    //and then this cfg flag go away
+    pub fn flushed(&self) -> bool {
+        self.flushed
+    }
+
+    pub fn blocked(&self) -> bool {
+        self.blocked
+    }
 }
 
 impl AsyncIo<Buf> {
@@ -103,16 +120,17 @@ impl AsyncIo<Buf> {
     pub fn new_eof() -> AsyncIo<Buf> {
         AsyncIo::new(Buf::wrap(Vec::new().into()), 1)
     }
+}
 
-    #[cfg(feature = "tokio-proto")]
-    //TODO: fix proto::conn::tests to not use tokio-proto API,
-    //and then this cfg flag go away
-    pub fn flushed(&self) -> bool {
-        self.flushed
-    }
+impl<T: Read + Write> AsyncIo<T> {
+    fn write_no_vecs<B: BufTrait>(&mut self, buf: &mut B) -> Poll<usize, io::Error> {
+        if !buf.has_remaining() {
+            return Ok(Async::Ready(0));
+        }
 
-    pub fn blocked(&self) -> bool {
-        self.blocked
+        let n = try_nb!(self.write(buf.bytes()));
+        buf.advance(n);
+        Ok(Async::Ready(n))
     }
 }
 
@@ -170,12 +188,14 @@ impl<T: Read + Write> AsyncWrite for AsyncIo<T> {
         Ok(().into())
     }
 
-    fn write_buf<B: ::bytes::Buf>(&mut self, buf: &mut B) -> Poll<usize, io::Error> {
-        use futures::Async;
+    fn write_buf<B: BufTrait>(&mut self, buf: &mut B) -> Poll<usize, io::Error> {
+        if self.max_read_vecs == 0 {
+            return self.write_no_vecs(buf);
+        }
         let r = {
             static DUMMY: &[u8] = &[0];
-            let mut bufs = [From::from(DUMMY); 64];
-            let i = ::bytes::Buf::bytes_vec(&buf, &mut bufs);
+            let mut bufs = [From::from(DUMMY); READ_VECS_CNT];
+            let i = ::bytes::Buf::bytes_vec(&buf, &mut bufs[..self.max_read_vecs]);
             let mut n = 0;
             let mut ret = Ok(0);
             for iovec in &bufs[..i] {
diff --git a/src/proto/h1/io.rs b/src/proto/h1/io.rs
index 55ef12ce..0b1b6dba 100644
--- a/src/proto/h1/io.rs
+++ b/src/proto/h1/io.rs
@@ -440,6 +440,9 @@ impl<T: Buf> Buf for BufDeque<T> {
                 return buf.bytes();
             }
         }
+        if let Some(ref buf) = self.bufs.front() {
+            return buf.bytes();
+        }
         &[]
     }
 
@@ -483,42 +486,54 @@ impl<T: Buf> Buf for BufDeque<T> {
     }
 }
 
-// TODO: Move tests to their own mod
 #[cfg(test)]
-use std::io::Read;
+mod tests {
+    use super::*;
+    use std::io::Read;
+    use mock::AsyncIo;
 
-#[cfg(test)]
-impl<T: Read> MemRead for ::mock::AsyncIo<T> {
-    fn read_mem(&mut self, len: usize) -> Poll<Bytes, io::Error> {
-        let mut v = vec![0; len];
-        let n = try_nb!(self.read(v.as_mut_slice()));
-        Ok(Async::Ready(BytesMut::from(&v[..n]).freeze()))
+    #[cfg(test)]
+    impl<T: Read> MemRead for ::mock::AsyncIo<T> {
+        fn read_mem(&mut self, len: usize) -> Poll<Bytes, io::Error> {
+            let mut v = vec![0; len];
+            let n = try_nb!(self.read(v.as_mut_slice()));
+            Ok(Async::Ready(BytesMut::from(&v[..n]).freeze()))
+        }
+    }
+
+    #[test]
+    fn iobuf_write_empty_slice() {
+        let mut mock = AsyncIo::new_buf(vec![], 256);
+        mock.error(io::Error::new(io::ErrorKind::Other, "logic error"));
+
+        let mut io_buf = Buffered::<_, Cursor<Vec<u8>>>::new(mock);
+
+        // underlying io will return the logic error upon write,
+        // so we are testing that the io_buf does not trigger a write
+        // when there is nothing to flush
+        io_buf.flush().expect("should short-circuit flush");
+    }
+
+    #[test]
+    fn parse_reads_until_blocked() {
+        // missing last line ending
+        let raw = "HTTP/1.1 200 OK\r\n";
+
+        let mock = AsyncIo::new_buf(raw, raw.len());
+        let mut buffered = Buffered::<_, Cursor<Vec<u8>>>::new(mock);
+        assert_eq!(buffered.parse::<::proto::ClientTransaction>().unwrap(), Async::NotReady);
+        assert!(buffered.io.blocked());
+    }
+
+    #[test]
+    fn write_buf_skips_empty_bufs() {
+        let mut mock = AsyncIo::new_buf(vec![], 1024);
+        mock.max_read_vecs(0); // disable vectored IO
+        let mut buffered = Buffered::<_, Cursor<Vec<u8>>>::new(mock);
+
+        buffered.buffer(Cursor::new(Vec::new()));
+        buffered.buffer(Cursor::new(b"hello".to_vec()));
+        buffered.flush().unwrap();
+        assert_eq!(buffered.io, b"hello");
     }
 }
-
-#[test]
-fn test_iobuf_write_empty_slice() {
-    use mock::{AsyncIo, Buf as MockBuf};
-
-    let mut mock = AsyncIo::new(MockBuf::new(), 256);
-    mock.error(io::Error::new(io::ErrorKind::Other, "logic error"));
-
-    let mut io_buf = Buffered::<_, Cursor<Vec<u8>>>::new(mock);
-
-    // underlying io will return the logic error upon write,
-    // so we are testing that the io_buf does not trigger a write
-    // when there is nothing to flush
-    io_buf.flush().expect("should short-circuit flush");
-}
-
-#[test]
-fn test_parse_reads_until_blocked() {
-    use mock::{AsyncIo, Buf as MockBuf};
-    // missing last line ending
-    let raw = "HTTP/1.1 200 OK\r\n";
-
-    let mock = AsyncIo::new(MockBuf::wrap(raw.into()), raw.len());
-    let mut buffered = Buffered::<_, Cursor<Vec<u8>>>::new(mock);
-    assert_eq!(buffered.parse::<::proto::ClientTransaction>().unwrap(), Async::NotReady);
-    assert!(buffered.io.blocked());
-}
diff --git a/tests/client.rs b/tests/client.rs
index 8183a1d2..523f1bcf 100644
--- a/tests/client.rs
+++ b/tests/client.rs
@@ -1044,45 +1044,6 @@ mod dispatch_impl {
         assert_eq!(closes.load(Ordering::Relaxed), 1);
     }
 
-    #[test]
-    fn client_body_mpsc() {
-        use futures::Sink;
-        let _ = pretty_env_logger::try_init();
-        let server = TcpListener::bind("127.0.0.1:0").unwrap();
-        let addr = server.local_addr().unwrap();
-        let mut core = Core::new().unwrap();
-        let handle = core.handle();
-        let closes = Arc::new(AtomicUsize::new(0));
-
-        let (tx1, rx1) = oneshot::channel();
-
-        thread::spawn(move || {
-            let mut sock = server.accept().unwrap().0;
-            sock.set_read_timeout(Some(Duration::from_secs(5))).unwrap();
-            sock.set_write_timeout(Some(Duration::from_secs(5))).unwrap();
-            let mut buf = [0; 4096];
-            sock.read(&mut buf).expect("read 1");
-            sock.write_all(b"HTTP/1.1 200 OK\r\nContent-Length: 0\r\n\r\n").unwrap();
-            let _ = tx1.send(());
-        });
-
-        let uri = format!("http://{}/a", addr).parse().unwrap();
-
-        let client = Client::configure()
-            .connector(DebugConnector(HttpConnector::new(1, &handle), closes.clone()))
-            .build(&handle);
-        let mut req = Request::new(Method::Post, uri);
-        let (tx, body) = hyper::Body::pair();
-        req.set_body(body);
-        let res = client.request(req).and_then(move |res| {
-            assert_eq!(res.status(), hyper::StatusCode::Ok);
-            res.body().concat2()
-        });
-        let rx = rx1.map_err(|_| hyper::Error::Io(io::Error::new(io::ErrorKind::Other, "thread panicked")));
-        let send = tx.send_all(::futures::stream::iter_ok(vec!["hello"; 2]).map(hyper::Chunk::from).map(Ok)).then(|_| Ok(()));
-        core.run(res.join(send).join(rx).map(|r| r.0)).unwrap();
-    }
-
     struct DebugConnector(HttpConnector, Arc<AtomicUsize>);
 
     impl Service for DebugConnector {