Answer from a beginner - measuring torque is going to be expensive. Big time.
I use a Cateye with wire that gives cadence, speed, ET, distance, and average speed. Cost about $40.00. I felt that having a wire dangling around that saved $100.00 was a status symbol in itself. Cateye instructions and quality are way better than the dept store breeds, by the way. The clock was a bit tricky to set, but otherwise straightforward. Be sure to calibrate your meter to your tire.
Some people are like a Slinky ... not really good for anything, but you still can't help but smile when you shove them down the stairs.