It would seem I have had a lucky escape, I have not had my UFM off the bike since I started using the Neal Videan seals, so all the inaccessible caps are still on standard sealing washers, and still using copper washers on the rocker oil feeds, I did have one tappet cap seal split, but I do like to check my tappets frequently and have had the standard tappet cover seals fail also. I suppose if you are really clever (as some are) you could recess the caps and O ring them, but I have always assumed that lowering the cap in the cylinder head could cause problems with the operation the rocker arm and maybe the valve spring clearance also. All the other V3 seals I have found to be excellent, especially the banjo seals.