I just got a Sigma 2209 for xmas-- it was really cheap, under $150 for the device and docking station and it comes with wireless HR, cadence, speed, barometric altimeter and *no* GPS.

Anyway I have two sharkfins on my left chainstay now because speed and cadence are unfortunately separate. There's no way I can mount them on the inside of the chainstay.. that would take a lot of tire/wheel clearance that I simply don't have. (Does it work on steel frames, maybe?)

However I do have them mounted on top of the chainstay to keep road funk to a minimum. I wasn't sure about that versus underneath. We'll see if I bump them while riding and if so, I'll move them to the bottom side.


Anyway, I find cadence really useful right now... since I've never had it. But after I put a couple hundred hours on the trainer over the rest of the winter, I will probably know my cadence by feel, and thus won't look at it much.