It does make it a pain in the butt without testing, yes. I know a lot are a fan of this practice, and I guess 5% average overfill helps protect against under fill, but it is a massive pain in the butt to get more precise dosing this way. I would suggest whatever vendor you buy from, look at the test advertised by the vendor and maybe split the difference if it is quite overfilled. Without testing though, there is no good way to knowA vendor advertises overfilled vials - Get more for your money. Does this not make accurate reconstitution impossible?