The CF Truncheon might be the best bit of kit ever. Pour in one part feed while you stir. Repeat every day for 20 years.. no problem.
If you loose the cap off a PH meter, it's as good as dead. I don't use a storage solution though. I tried. It fell over. I shook my head.
A couple of flicks with the wrist clears off most fluid, then pop the cap on. It should last ages. Anything else has been a fail.
I had a lot of use out of a scan2 and don't understand why they were withdrawn. My phtestr 10 must of done 4 years on it's current tip. Also a withdrawn item. It's getting slow now. Maybe 15 seconds to stabilise. You can see where it's heading before that though, and it keeps it's calibration well enough to not bother. It might be a year since it was last checked, but I know it will be within 0.2 I have had it so long.
I do like a waterproof meter. This means they spend a lot of time bobbing around, which may contribute towards them staying alive. A properly designed meter really should be happy getting a dunking. If it's not happy swimming about, then I wouldn't expect it is fit for purpose. I would go as far as to say, if it's not waterproof, it's crap. I have had a few such meters, and non lasted. I'm not sure it's a case of getting what you paid for, so much as getting something that uses choice components. Waterproof. Easy calibrate with 3 points if you wish. Replaceable tip. If it's all those, you won't need another tip. What were measuring is really quite weak.
I killed one unexpectedly measuring RO water once. I don't have a solid explanation of why. I guess it sucked (the ro water, that is)