Just because a few owners have some serious reliability issues doesn't mean it's endemic (either within a specific vehicle or a wider brand). As above with the Mercedes example, it sounds like the problem was diagnosis not repair as such. I suspect the same with the OP. I realise the OP is frustrated, but it's unlikely (I would have thought) for VW to "bodge repair" because while the vehicle is well within warranty, that dealer would be accountable for any subsequent failings and if these were due to poor workmanship, I suspect the dealership themselves would have to shoulder the cost, rather than it being recharged to VW UK as warranty work would be normally. In the case of the OP I wouldn't be surprised if there's been an internal standoff where the dealership keeps saying to VW UK "we have tried x and y, still doesn't work, can you authorise a new engine" (or some other major overhaul), VW UK then says "no, we're not authorising that, too expensive, keep looking". Rinse and repeat, not that it helps the poor customer in all of this of course!