I didn't realise this was still a problem. I bought a Tern Verge x10 about 5 years ago, and although I was aware of the recall on certain frames, my serial number was not affected, and I rode my bike pretty hard for nearly 5 years with no issues. However, around a year ago I had the bike turned over to do some work on it and noticed a crack right along the weld at the fold where a lot of these frame failures are happening. As soon as I saw that I decided it was far too dangerous to ride and contacted Tern to get a new frame (I was literally one month from being out of warranty). Thankfully, Tern accepted liability and allowed me to simply take my bike to a nearby bike shop, who sent the bike to Tern for a new frame. I got it back in a couple of weeks, no problem. However, the new frame has the same design as the old one, not one of the more modern x10 frames, so I'd imagine it will suffer from the same fate as the first one in less than 10 years. At least my frame failure was gradual and I caught it before it actually broke. To be fair, I sometimes rode with 15-20kg in my backpack (and I'm 85kg), and once rode down a mountain path on it, which may have contributed to the failure... but glad I did, because if I didn't, it probably would have cracked once the warranty expired and I'd have been SOL.
The x10 has actually been a nice bike to ride, but the issue of frame failures did weigh on my mind when I was riding from time to time (usually when going fast downhill, or on a road with a lot of traffic) and there were some design flaws that annoyed me a lot. I'll just get the design flaws off my chest here
- The chain cannot be trusted to stay on. Current models might have less problems, but my chain fell of so much it made riding miserable until I had to pay $15 for a plastic chain stay from Tern that more or less solved the problem.
- Folding is quick, but the fold design is awful and less convenient to carry than when not folded - it's very easy to carry unfolded!
- The magnetic fold lock is total crap. The magnets never line up perfectly and don't have enough force to keep the bike reliably shut.
- Brake cables were rubbing on the frame and wore a grove into the front fork before I noticed (I guess I should have paid more attention)
- Officially recommended mud guards from Tern were expensive, poor quality and not properly designed to avoid the brakes. Maybe for newer models?
- Can get quite creaky. I think it's an issue with the seat and length of the post, as putting some oil under the seat reduced squeaking.
Anyway, I wouldn't buy another Tern based on their reported behaviour in this thread, even though they did sort my bike out pretty quickly when I contacted them (this was Tern Japan, btw, which may have better customer service than elsewhere).