Have been having some problems with my long used combo of an Android phone plus Wahoo Tickr HRM and Runkeeper. First of all the phone manufacturer "updated" the operating system of the phone and broke Bluetooth 4 LE support in it, which then meant that my HRM can no longer talk to the phone - and then Runkeeper issued another of their innumerable "updates" which has caused me to have GPS problems.
So - Garmin have fairly recently released a new FR230 HRM watch to replace the previous HR220 - so the HR220's have come down in price so I bought one - still cost me $300 though!
Have had only one use of it yesterday - at parkrun. I wanted to do a 5K non-stop at 7 mins per K as I will be running in a 10K in 2 weeks time and am aiming for a goal pace of 7 mins per K for that. I did this particular race last year - trained to do it run/walk at 7 mins per k and finished up running it non-stop at 6mins 20 secs per K. I have always severely doubted that time because , after the race when the results came out , there was no result for me - 24 hours later there was a result for me ( at a time that I can't believe! ) - Anyway - at parkrun I used the pace band facility of the watch - got it to beep/vibrate at me at 7:15 mins and 6:45 mins and that kept me fair square in the middle of the band at 7 mins. It is just a pity that there is only one sound tone for each alert - would be better to have a different tone for each end of the band