Review on 🏃 Polar Vantage V" - The Ultimate GPS Multisport Watch for Triathlon & Multisport Training with Heart Rate Monitor, Running Power & Waterproof Design by Debbie Thomas

I've been wearing Polar since I bought them in 2003 for my first marathon. I've tried other brands but always chose Polar. I love the Polar Vantage V for its features and ease of use, but since Christmas (when I got it) I've had some issues with a 30% higher calorie burn rate than my Polar A-300 during exercise, so I don't know it is simply more accurate or sensitive than the A-300, or has the firmware/software changed. The other issue I had was that it factory reset two days ago 01/02/2020 and all I did was wear it (no button presses or anything) and I had to go through the setup procedure ran it again and through the next night it didn't collect any sleep data and gave me a notification to wear the watch for at least 4 hours while I slept, which I did. I'm debating whether to return it now or give it another chance before the returns window closes.