Interesting question.
I haven't had any niggles that I know some owners have had. The fit and finish are pretty good and it seems to be wearing well.
I managed to fry my engine though. Head gasket went boom and the block warped. Not Good! I'm not too upset as I had some good advice to expect it to behave like a supercar and salt away some cash for an engine rebuild one day.
I love the looks and the sound it makes, but it is a little uncouth for a daily driver, but perfect for highdays and holidays.
TVR have had some problems with inconsistent engine build quality, some are great and have no probs, there are a few cerbs with over 130,000miles but there are also a few with significant problems. That's not to say it's unusual with powerful cars - visit the 911 forum on pistonheads and ask about 996 engine reliability if you want a hard time . But TVR could do a lot better with customer service and warrenty hassles.
All that said, I don't regret buying it. The ability to polarise opinion of everyone you meet - love or hate at garages, abroad, hotels is eye opening and good fun. As an experience the acceleration and wail above 4000rpm that's makes women in the passanger seat sqeak is one to be remembered into my dotage.