Might depend on the quality of the rubber as well. Suffice it to say, I make sure there's a few drops on the little soldier before he puts his helmet on ever since I once got so irritated that I needed ointment.
Amount of lube applied before putting on the rubber can make or break the intercourse, Too much and it slips off, none at all and it gets so dry on the inside that you lose your boner and/or get irritated.
