I'd like to get a computer that tracks the usual (speed, avg, time, etc) plus cadence, plus heart rate. I would also like to be able to download the rides so i can graph the heart rate across time, speed, cadence and distance that way i can compare my heart rate to various points in my standard rides or in looking at interval performances.

Garmin 305 the only option?

Problem with that is that i'd rather not spend that much money because i eventually plan on getting a PT...