I use a Sigma 2209 (wireless)...it has a HRM, speed, cadence, even an altimeter but I don't reference it that often. I've had very little problems with it. Every now and then, my cadence sensor might get bumped out of whack...but it's not a big deal. I just have to fiddle around with the sensor to get it in the "right spot" with the magnet in order to pick up the signal, but then it works fine. It usually only happens when my foot accidentally hits the sensor and knocks it out of whack. It comes with it's own HRM strap that is fairly comfortable. I've worn some HRM straps that were really uncomfortable, and the Sigma one is fine.
2012 Seven Axiom SL - Specialized Ruby SL 155