I have herd of a couple of these now, Revo's K1 been one of them and an S3 apperently so an APR pump might be on the cards, also headgaskets seem to have gone on a couple of cars all needing new engines
Talking to INA the headgasket is above industry standards and its the bolts which look a bit weak so maybe ARP bolts might not be a bad idea for longevity. I think there around 200 USD shipped to anywhere in the UK.
Maybe stage 2+ is starting to catch up on a couple of engines.
Off to go smell the dipstick now.