Never had a problem with Vesrah gaskets, make sure none of your gasket surfaces are warped and also make sure they are very clean, like spotless. When you tighten stuff down, use the pattern that the service manuals recommend as well. And never use silicone except for the cylinder head cover where it doesn't use a gasket but calls for a semi-drying gasket sealer.
Trikes
1984 Honda 200x, 1984 Honda 200m
Bikes
1995 Honda CR125R, 1985 Honda XL100 (gone), 1982 Kawisaki KZ550 LTD,
2001 Yamaha TT-R 125L, 1983 Honda XL185S (current project), 2001 Suzuki SV650S