I just got one too, and it's really amazing. It says you can't have the speed sensor more than 50 cm from the puter if i recall correctly, so i don't think the rear wheel would be an option. the cadence sensor has to be no more than 80 cm too i think.
Anyhow, setting it up was easy, and trying it out was super fun. Going from a cateye simple 20 dollar gadget to this thing was like getting hal 2000 attached to my bike. I love the lap function, the little bars for heart rate and speed, the file summary function, and then the cool wireless transfer to your puter through the speakers!!! that's just insane, really.
My only problem has been trying the "ownzone" thing. I can't get it to record past the third bar on that, it always goes right into a lap program after 3 minutes. anyhow, i can just use the actual hr number to compare with my zones and work it from there.