So far, the only one that worked well for me as I have issues with straps, is the Mio Alpha watch. Even my husband who is a fan of the strap no longer wants to use his so I order the Mio Alpha 2 watch (for me) and he's keeping the Alpha watch. Very very satisfied. It links to my kinetic app but it will not work with my Polar CS500+c. But that is ok. I don't need to look all the time at my screen when cycling. It is just a guide for me and not a full-working tool.
Like trainer said... unless you have a heart issue (which is not my case), you do not really need a HR monitor. Your legs will tell you even before your heart that you've had enough.
Helene
Riding a 2014 Specialized Amira LS4 Expert - aka The Zebra!
2015 Specialized Crux e5 - aka Bora Bora bike