Made the switch about 2.5 months ago. Had a FR245 which didn't handle multisport. I was ok with it for running (also got a stryd that made it muuuuch better on the treadmill) didn't use it for the bike and really liked it for swimming in the pool (loved that I could basically build a workout, hit go and have it walk me through and record everything as I did it, no more index card in a ziploc). I moved to a Vantage V, and have been happy with it. I now use it to record everything. I wanted to try and see if it could basically be my one stop shop and use Polar Flow instead of training peaks to save $120/yr. I have had to learn a new ecosystem, and sometimes hit the wrong button and there have been a few things here and there that I had to figure out, but overall it's really nice. I'm not sold on being able to ditch TP yet. I really like the sleep/recovery metrics quite a bit. The Nightly recharge has been excellent and i've learned a few things from it that I think make my recovery and subsequent training more effective. For example, two beers and my sleep suffers, but because of the way that Polar breaks it down, I've learned that I can overcome that deficiency with a little more sleep. So it's kept me from drinking on weeknights when I can't get an extra hour or two.
Honestly , the swimming is the only thing I felt Garmin did better (I don't get missed laps, but the garmin interface and data I'd upload was just much better. I'm learning to deal, and realize that an index card in a ziploc isn't a big deal. The polar has an auto pause so it senses when you are resting on the wall, so now it's more like swimming when I was a kid, using the written workout and a pace clock.
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