TBH that's maybe a few dozen or so out of 100,000+ sales. If mine went wrong would I be unhappy? You bet I would, but one of the major differences between the USA (where almost all of the failures have occurred) and here is that in the UK Festool UK will generally have your tool picked up withing 24 hours and back to you within a week. The USA being so much bigger they aren't able to offer that kind of service because I think they only have a single service centre (but I may be wrong about that). By way of comparison if a DW or Makita goes wrong over here you can be stuck waiting for parts for 4 to 6 weeks before the local dealer even starts on the repair. Bosch and Hitachi are no better and Metabo are generally far slower. That's something I know from experience
I, too, was very wary of buying the Kapex because of these reported issues. I carefully read all of the comments, as well as the comments by guys who said that if theirs went down that they'd buy another one - note that, they'd happily buy another Kapex rather than a DW or a Makita or a Hitachi, etc. It's because they are so much easier to use, more accurate and less (far less) dusty. In the end what decided me was that I knew three other guys who'd all been using them for a number of years (the longest being 7 years at the time). None of them had had issues, and none of them knew anybody personally with a Kapex who'd had issues. Same went for the local dealer at that time who'd had one Kapex back out of more than 40 sold with a suspected motor issue. That turned out to be the user's site transformer which was a PoS (undersized and basically old and knackered). And if you are having problems with a Kapex in the UK, that's where the issues will possibly be (for some reason the motor problems don't seem to happen with 230 volt models). Anyone who remembers the old Elu and DW flip-over saws will remember that they used to eat start/run capacitors if you insisted on running them on an undersized transformer with undersized cables. It means that I have a 5kVA transformer, I don't share it with anyone else (to the point of removing offending cables and chopping the plugs off for repeat offenders a couple of times, a perk of being a foreman), I have a decent 32Amp (4.0mm section) cable and I only run one extension bit of electric string (i.e. one cable only) - not the half a dozen or so daisy-chained together some idiot site managers think is OK (it isn't, ask any qualified sparky). Oh, and I don't share with anyone on the grounds that there some absolute muppets out there calling themselves joiners these days (well, there always were a few) who can break anything. So most of the time I don't have problems. That said I don't take the Kapex out to do rough first fix - there are better tools out there for that