So for anyone interested, my Dad's Skoda went for the recall recently, it's the 2.0 litre TDI with 170 BHP. He hasn't driven it enough to notice a difference in performance, and he doesn't do many miles so doesn't track his fuel usage unfortunately. Will update if he mentions anything.
But the service from Skoda was excellent, they said they would arrive at the house at 11.30, and they arrived at 11.30 bang on. They gave my dad a brand new 2017 Octavia for free and took his car back to the dealer, some 100 mile round trip. Then the car was returned a day or so later, fully valeted, emission control fixed and some free gifts thrown in too. I am sure this is better service than you'd get with VW and the scandal was their fault. In a way I feel sorry for the sub brands like Skoda, Seat etc who still feel they have to redeem themselves when it was more to do with VW. Skoda is now the most reliable brand you can buy in the UK according to consumer reports.
My brother will be trading his 2012 VW Golf TDI for a 2018 Golf R in September. The dealer promised $5,000 to him on top of the car's Blue Book value; so $12,000 plus $5,000. In addition, he received $1,000 a year ago.
Originally he was planning on keeping the car for 10 years, but he is worried about resale value and testing regulations that might be required in the future.