On Thursday last week one of my vintage VDO computers (wireless, has speed and cadence magnetic sensors, over a decade old) kept stopping recording distance and cadence. I changed the three batteries in the sensors and the computer part on the handlebar on Apr 26. Thus, about ten weeks on the batteries.

Last year I used that bike for a bike tour, the computer was outside the whole time, and several days of rain. And it was showing a lot of moisture inside the screen for the rest of summer. By end of winter the moisture condensation was no longer present inside the screen, but I think my computer is toast. Have the same one on two other bikes, so far those are still waterproof.

I found this today on Amazon, looked like a great replacement for my VDO computer at a fantastic price, until I read the reviews:
https://www.amazon.com/product-reviews/B083SJYL9K/

Reviews told me to not buy it. I like having a separate computer from my GPS, I often leave the GPS at home for rides near home. Looks like I might have to start putting more user time on my Garmin GPS.

I have some wired ones in storage that should still work, but they lack cadence which I would like to have.