"I have a high risk to have an issue in three years from now with the MOT..."
change them back in three years...
I already have the S&S stealth air intake with the Muscle Cover. Next are the Garage 56 exhausts. And I'll keep the standard ones so the day I'll pass the MOT I can change them back if needed.
But chaging the cams is too much... a non-reversible job for just passing the MOT...