VW is flooding the market with them right now, so there are lots of options to choose from.
I don't know that I would have a problem with how long the vehicle sat with VW - Look at every unit as an individual. Let the car tell you how it was treated. Pull the carfax / get dealer records if you can. Obviously drive any candidate, but also get under and look at the underbody, the crevices in the engine bay, places that are a bit harder to get a detail rag into. Lift up the rear cover and look at the spare well. LOOK FOR DIRT / GRIME / GREASE. If it looks like it hasn't been maintained where the detailer's rag didn't go... Think about moving on.
Feel the seats. Press on the dash / panels / doors, looking for looseness or squeaks or things that maybe don't fit right or feel solid. VW's interior fit and finish is quite good in these, they should still be quite solid.
LOTS of owners, knowing that they were going to give the car back to VW and NOT knowing what would happen to it... They simply stopped doing maintenance on the cars. Your new purchase SHOULD include a plan to replace ALL the fluids as soon as you get it. It SHOULD include a plan for new tires. VW will NOT have done either of these. They "MIGHT" have replaced the DPF, but if their scan showed that it wasn't full... Then they might just have passed it right through for sale.
Beyond that.... Every one of these should be under warranty for every part that touches fuel or exhaust. So that is a LOT of expensive components. Interestingly and notably, the transmission is specifically excluded from the extended warranty, although with proper maintenance the DSG has been a good performer. I also have not had issues with the 01M on the older MK4 cars b/c I did the unthinkable... I changed the fluid on a schedule and kept it from running hot!
For these, the new warranty is the LONGER of (4 years / 48k miles from date of modification) OR (10 years / 120k total miles from original in-service date)
So if the car already has over 120k miles, it will be covered for an additional 48k. If it has less than 120k, then it will still get another 48k if it has more than 60k, or up to 120k if you find one with about 20-40k on it.