I am quite liking my new Garmin 220 with the latest Gramin soft strap HRM. I have used other HRM's before - including one which I thought would be good - a Wahoo Tickr , but until now I have had problems with strange and unpredictable readings. So far this Garmin strap has not once shown a weird reading. BUT - I am washing the strap after every use, so I don't know if this is the reason or maybe the strap is simply "better" . One thing I can easily see is that this Garmin strap has two pads on either side of the chest.
I have been a bit surprised at how high my HR gets sometimes - so I have been using the HRM to deliberately hold myself back. I did this is in my recent 10 K "race" - where I held myself back for the first 5K by having the HRM beep at me (loudly) if I went over 145 BPM but then ignored it during the last 5K . I felt that I finished the 10K strongly. Over the weekend I did a similar thing at a local parkrun which I only ever once per year at Easter( it is alongside the ocean) - held myself back for the first half and pulled out the stops for the last half. I finished it in a time 1 minute slower than my PB on this course last year - but I feel better for it. I want to run these distances "strongly" and finish feeling good about it and keen to go onto my next training run - rather than to try for irrelevant (to me) PB's.