I’ve had no problems with my VS3135 watches. Not so much for my VR3135 watches as about half are poorly assembled. I have no experience with the IPKF ETA clone movement.
Also, choosing movements you should consider what your end game is. Do you see yourself modding or building a franken watch.
Using the ETA you’ll have issues with Gen parts. Most aren’t compatible and some aren’t compatible without modification.
Then there are service issues.
Asian knockoff ETAs are supposed to be cheaper to service but don’t be surprised if your corner watch dude says he/she/it/etc can’t, or won’t, fix your watch.
Fortunately, the cost of clone 3135 movements is low enough that replacement is no big deal if you ticker craps out.
Free advice and worth every penny.