My white project is bored over 1mm (86mm now). I know OEM headgaskets are great quality, MLS type. I knew from previous 1st-hand comparison (curiosity) that the F23ax and F22ax headgasket are very similar and only in one corner there is a coolant port you need to drill out on the F23ax to match it to the F22ax HG. I obviously did that, have no issue with engine temp/coolant system after 350 miles accumulated so far. I also do not have any compression leak issues, as I did a leakdown test (better than compression) and am in the 3% loss, which is good. I'm sure Bisimoto's HG are good too though and I would go with his for anything 87mm+, since I know of no OEM HG that would work.