Lifetime design means it is meant to be designed to last the the life of the vehicle, whatever interval they use for that. Should be at least 100,000km or 6 years. Obviously even with a lifetime design (as the DSG clutches), they are only as good as the length of warranty.

Water pump longevity surely depends on if the multi-V belt tension is correct. Would have to test the tensioner.

Sounds like extended warranty is the go for VAG.