I also have the Polar FT4, and find it's a great little motivational tool to go just a little longer, or try to work out just a little more intensely. I feel it sometimes overestimates calories a bit because once I get my heart rate up, it doesn't go back down much even if I ease up on intensity, but I think that's a personal problem rather than a Polar HRM problem.
Do some research on what features you want based on what type of exercise you do. Polar's website lets you compare different models and sort by waterproof, whether it has a training program, how long it saves data so you can look at your progress, etc. If you run outside you may want a GPS model (I've seen Garmins recommended for that). No matter what you pick, get one that has a chest strap. If it doesn't have a chest strap it is basically just guessing, and you can do that for free.
Do something everyday that your future self will thank you for.
| current weight: 179.8