Personally, I have seen many more issues with Schwintek slides posted on RV forums than any other system, even the new "improved" Schwintek. From what I see and read, the HWH hydraulic system seems to be less problematic, but your mileage may vary. My HWH system had an intermittent problem when I bought the RV (used) last year; turned out to be a simple bit of corrosion on a fuse; so the electric portion, not the hydraulic. 12 years old, so I guess I can understand. No issues since.
Bottom line is that slideouts are just another "system" on an RV that can and may give an owner problems, no different than any of the other "systems" on board. And just like any other system, care and maintenance can go a long way in reducing (not eliminating) the chances of a breakdown/failure.
