TP only good if you are going to monitor power output, and then only if you have the time, inclination and a degree in sports science to understand it. In the end I found it was more data than I could deal with (and I was riding on the road, so easier to stay at certain levels and cadence) and my HRM data still gives me key info like threshold, cadence, GPS data etc.
If you are using a HRM instead, lots of excellent (and cheaper) alternative software around. I have used both the Polar Personal Trainer (V5) and am currently using Sports Tracks Linky Link Linkand find it really useful (for training) and very interesting from a GPS point of view – it’s matched with a Garmin 500.
Hope this helps