I have the FT7. One thing I do not like is that the chest piece has to stay relatively close to the watch. I had wanted to leave the watch next to where I do my swings so that I don't need to be wearing something on my wrist while doing the left handed swings. It's not a big deal, but hearing about the bluetooth ones where you can display it on your phone without having to wear a watch piece makes me think those would have been better. Also, after reading about HRV in the later discussions in the awesome "HR monitors for the data averse" thread, I wish I had a way of measuring that.
I REALLY have benefited from the FT7, and I don't want to take anything away from it in that regard, its just that there are other things I didn't know to look for at the time, like the distance the chest piece transmits or the ability to track HRV. The FT7 gets the job done as far as being able to use your HR as a cue to begin the next set. Less concern about overtraining by going too soon, or delaying progress by resting too long. I really should be learning the intuition and self awareness of where to start though and not use the HRM as a crutch. I'm going to start guessing when I'm ready without looking to try to work on that, and then check to see if I still need to wait a few breaths or something if I'm off.