I like the sound of the models with different coloured LEDs for different HR zones, but can the zones be set manually? I used a polar chest strap years ago and my HR was never anywhere near what it "should" have been.
I assume that if I go for that model then I need an armband, but in the absence of a bulging bicep, will the armband stay in place, or slide down?
Even rowing topless (not a problem, I only ever row at home) would I be able to see the lights on a chest strap - or do they show up on my phone, with the appropriate app?
And if paired with the PM5, can anyone show me what the display looks like? (I need to see as many numbers as possible so I can do mental arithmetic to pass the time

Thanks in advance for any insight or further suggestions