I've had Cateye and a I have a Sigma with wireless cadence (don't remember the model off hand) and my favorite is still the cheapo wireless sold under several brands with different packaging.

Here's the Nashbar version: http://www.nashbar.com/profile.cfm?c...Cyclocomputers

Here's the Ascent branded version: http://www.nashbar.com/profile.cfm?c...Cyclocomputers

The drawbacks are that the maximum speed sometimes gets a flakey reading and it doesn't have cadence. Otherwise, they've been reliable and I like the fact that you can set it to cycle through the readings so you don't have to diddle with the buttons to check your average speed after checking your time.

The most annoying feature of the the Sigma is that you have to individually reset your trip distance, trip time and your averages before a ride rather than having them all zero together. Oh yeah, the o-rings suck too.

The Cateye is a bit less functional than the Nashbar, costs more, and won't automatically cycle through the measurements.