Pure folly to think that an internal gasket cannot harbor bacteria. We use airlocks to keep the bad stuff out...if bad stuff is present when that lid is put down, it could surely get into the must/wort. I never used anything but glass carboys during brewing, but when the wife wanted to do some wine recently, I did turn to the plastic bucket. Very easy to put a little pressure on the lid and remove that gasket for cleaning. Take the 15 seconds to do it.