Advice on new HRM....

slieber

My Polar F6 is, I think, dying. I know the chest strap is over two years old and likely ready to go anytime. I replaced the watch battery and the jeweler didn't seal it, so I sealed it with silicone and now it occasionally has "brain freeze" where the screen goes blank and it loses whatever data has not yet been stored - it does this even if I'm not exercising or anything.

So, I had planned to get an F11 but I notice they're discontinued and replaced with the FT40 (?). Recommendations? I use my F6 religiously in my workouts - I'm not addicted but I do like to know how hard I'm working and what cals happen, etc. Can I get by with a leftover F11 or should I just get the newer one?

Thanks for any advice.