Garmin doesn't really offer any features I want that justify even the 20$ more the 520 costs here over the bolt. Personally I don't feel like giving them a second chance, they seem to be doing fine without my money
I wouldn't pay 150$ more for the 830, not sure what features it has but I don't use any of the fancy features like VO2 estimates nor do I trust an algorithm to tell me how well I'm hydrating or sleeping. If wahoo jumps the shark, there's other people making head units now. Literally I just want my gps to record my ride data and tell me when to turn. I carry a battery for charging my phone so I don't really care if the gps battery only lasts 12-15 hours, I only do a few rides a year that are longer than that.
I've been lucky with wahoo support, they gave me a 50% off code for a new unit back in 2019 when mine was experiencing crashes on long rides. I threw out the box/receipt after the 2 yar warranty but if I hadn't they were gonna give me a new one. My tickr has been solid for a long time, and they were very quick to swap out my kickr when it started making noises, even though it was a refurb. I had a replacement in a week, they shipped it as soon as I dropped off the broken one at UPS.