Well, I've bought a Tiguan!
Phoned the sales fellow about the mileage discrepancy and agreed we'd sort it out when I visited. Check online prices and even at hight miles it was still well priced for a main dealer car.
So, yesterday my wife and I took it for a test drive. Car is one previous owner, taken as part-ex at another VW dealer in the group. As you'd expect, all fine. Still not convinced about DSG but I'll go with it. Car itself had a small dent on door, chipped/scratched plastic on wing mirror casing, small scuff on bumper. They said at the price quoted they'd fix the paint but not the mirror casing. Wheels immaculate, new tyres on front, back ones a bit thin but okay.
Prepared to argue about price/miles but made aware that car had some extras over and above standard SE NAV spec - winter pack (heated seats & washer jets), sports seats (with massage!!), rear facing camera, retractable tow bar (£1000+ option!) - which the dealer assured me they hadn't known about when they priced the car, and I believe him.
So, I came to a conclusion that it was a good buy at the asking price, and I was fairly certain they weren't going to budge, so told them if they would fix the paint/damage, including wing mirror, I'd take it at price asked, and the deal was done. Pick it up end of next week, maybe sooner.