Here's another cautionary tale...
I bought a 2010 MK6 GTI with 108,500 miles (CCTA 2.0 L 147kW engine; DSG gearbox) at the beginning of May (2017). In GREAT shape. My mechanic said it had the wear of a 2014-2015. All parts tight, no visible leaks, oil pristine clean, ran great, etc. almost no wear anywhere - body or interior. Fun car to drive. (Out accelerates my son's Hyndai Toscani ed. V6 Tiburon!) Every once in a while, I heard a "dieselly" noise on startup. Not much, and not too metallic sounding. I've read the threads on the tensioner issue, and was concerned; but not to worried...
Three weeks and at about 109,000 miles, I pulled into Walmart after driving home from work (about 40 min), and the car started bucking at idle when I parked it. No prior warning of a problem. Went right home w/o shutting it off. Tried to start it about 15 min later, and it bucked and made noisy clacking noises and would not start. After revving it, I got it started and had a friend read the error codes. About 15 of them. The main one one was for timing and misfires (P011 or something). Drove it to my mechanic. He didn't have the tools so towed it to VW dealer.
They confirmed a timing belt tensioner issue. Quoted me $4600 to repair it. Luckily no bent valves. Told them about the SB VW has on this issue. They were able to knock the price down to $3800 depending on what they found when they got into it, with the hope that if the bridge screen was intact, I could save $800 on a camshaft replacement. No such luck. Screen missing. VW recommends intake camshaft replacement in that case. All told: camshaft timing chain, chain tensioner (06K), chain rails, intake camshaft, chain adjuster, oil change. Mechanic did confirm the original chain had stretched. The dealer was very willing to work with me to extent they could. They even loaned me a 2017 Jetta SE while mine was in the shop. (Nice car - only 890 miles on it!) All told $4011. All the more painful as I hadn't had the car long enough to have even researched the issue much. I do like the 12k, 1 yr warranty, though.
Keep in mind - the car was maintained as meticulously as possible from what I've seen (I don't have the maintenance records; but even the paint job looks like it was just off the showroom floor.) There was no indication of sludge or dirt in the oil, either. So I'm not sure the oil is really part of the failure mode. At the most - it could hasten the issue if you don't change it regularly, I suppose. (I agree - 10K oil changes don't make much sense to me, even though VW insists that is normal and perfectly OK...)
Had a scare not 24 hrs after getting the car back last week. Stopped to update my mechanic on the issue, and when I started it up, I got the loud rattle/shake and it wouldn't start. Started it again, and no problem. Took it to VW next day - no error codes, and car sounded just fine to them. The mechanic was worried about it so kept it for a while to see if the issue showed up again. Nothing. In the past week - car still fine. Best guess - just an anomaly. So fingers crossed.
Bottom line - this can occur to anyone regardless of how car is maintained, and at any mileage. If you have a car on the SB target list - go direct, do not walk, do not pass Go, do not collect $200, and have the chain tensioner replaced as preventive maintenance. It is a lot cheaper than fixing it after a failure. I was lucky. I didn't have to replace the engine; but $4000 after literally just spending 10K on buying it? Very painful. Not a happy camper. I will be writing VWoA to see what they say. Will also see if there is a class action suit I can get in on. This really should have been a recall. Or at least VW picking up 50% or so of the costs...
Makes it difficult to justify keeping the car, though I will. At least for now. Made for a hell of a week, though... <sigh>