Whaoo Speed/Cad sensor, definitely. The Chinese ones are hit and miss (I have one that starts giving weird readings on hi speed descents, but reads fine otherwise).
For HR I have a Mio Link (the scosche Rythm+ and the new Whaoo are also good). I actually take mine out of the band and have it on my quad under my cycling/tri shorts (works great).
ECMGN Therapy Silicon Valley: Depression, Neurocognitive problems, Dementias (Testing and Evaluation), Trauma and PTSD, Traumatic Brain Injury (TBI)