Garmin
Forerunner 255 Series
Long battery; but wrist HR tracking is inconsistent.
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Ha! This post took me on a trip down memory lane! I had to look at my history in Garmin Connect. Started using my Garmin Forerunner 305 back in 2010. Since then I’ve upgraded 3 times: 310XT in 2012, (loved this watch), 235 in 2019, 165 this year in 2025.
That's what I do and works fine, the screen is a little small on my Forerunner 310XT. But I bought it used years ago for 100$ and got the little handlebar mount thing.
I've had lots of Garmin computers and lots of Garmin watches. The two aren't really compatible. First started out with a Forerunner 310XT many moons ago that I strapped to my bars. Lasted about a week before I got an Edge 200 and I've had a seperate running watch and bike computer since. You really don't want to be looking at your wrist all the time when you are cycling and as I've gotten older and need reading glasses a watch on the bars isn't suitable for me anyway. Also there's a lot more real estate on my Edge 1050 compared to my Fenix 8 so lots more data to be seen and I can see different pages of data with a swipe of my finger as well as a navigation screen. I've also got a Varia radar that makes an audible beep on the computer and gives a graphics indicator of approaching vehicles.
Until very recently I'd been using a Forerunner 310XT that I probably had between 10-15 years! I only stopped using it because the casing broke to the point I couldn't get a wrist strap to attach to it anymore. I couldn't be bothered to try to fix it and didn't fancy holding it in my hand while running, or keeping it in a pocket, so sold it on as good for spare parts. I'd already got myself a Galaxy Watch for daily use so just use that as a running watch too now. I'm not sure it's quite as good as displaying the info I want/need while running but that could just be a user/config issue. It's more than adequate so I'm in no rush to upgrade to another Garmin.
I've never had much issue with battery life on my Garmins - currently a Fenix 6, a couple of Vivoactives before that, and even a 310xt _way_ back. But I also wear my Garmin against my skin, so it tends to get covered with base layers while I'm actually skiing. I just roll back my sleeve if I need to interact with it.
The other thing that is noteworthy for me about Garmin is that I find the customer service incredible. If there is any issue with your watch/power meter, etc, support is great. Once you get through the "reset the device" nonsense, if it still doesn't solve the problem, they just send you a new refurb. Even if it's out of warranty. I had the FR 205 brick on a wrist. The sealing on that was shit and sweat seeped into the watch. Boom, new replacement. 310XT, the plastic on the buttons would wear through and water leaked in when swimming. Yep, new repalcement. Heck, I had a pair of Vector pedals go bad and not only did they send me new ones, they sent me the Vector 2s. They have my lifetime loyalty and goodwill for that, across 20+ device purchases for myself and my family.
Garmin
Forerunner 255 Series
Long battery; but wrist HR tracking is inconsistent.

Garmin
Forerunner 955 Series
Best value, clear MIP screen; limited smartwatch features.

Garmin
Fenix 7 Series
Durable, multi-week battery, flashlight; high price, buggy software.
Garmin
Instinct 2 Series
Rugged, solar multi-week battery; bulky, small screen readability issues.

Garmin
Enduro 3
Multi-week solar battery, lightweight; but bulky form factor.

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Garmin - Forerunner 255 Series

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