My IPV mini (30w - same thing) is over a year old and works just as well now as the day I pulled it outta the mailbox. Mechs? If those work well when they first arrive, they'll never be a problem. If they're a PITA right outta the mail, they'll be garbage forever after lol
My Coolfire IV's are too young to really gauge, but the oldest of them is about three months old, and still works like a champ. The finish on the purple one was getting a little dinged up, but I put that one through hard use (Crammed it into a bike pack with a phone and keys and a tank), so that's expected...I put a JWrap on it, and it looks better than ever! Still works great.
MVP 20w - a year old, still works just fine. I just hate the button placement and the fact that I can't put a sub-ohm RDA on it, but it is what it is...
EPower variable voltage only - the ego connector's is getting a little floppy, but it still works.
2 Vision Spinners (original version, not that cockamamie version II) - WAY over a year old, and I keep them to give away to newbs who show an interest in vaping. They work just fine.
I've been vaping for a little over four years now, and it's been my experience that most PV's last a little over a year before the internal, non-replaceable battery can't hold a charge anymore and has to be tossed. Notable exceptions: The Vision Spinner II (had charging issues from get-go-one) but that's along the same lines as everything else. If it works great at first, it'll probably go on doing that. And if it doesn't work well when it's brand new, it's gonna get tossed in a few months when I lose patience with it.