Short answer: I think there's likely to be *much* less variation in mouthpieces, as long as they're made of pretty much the same material... Falling quality is usally the result of cutting costs, usually in terms of man-hours or materials. Looking at mouthpieces, it seems to me that once you have the design frozen there are only two ways to reduce the cost: automate the process or change the material. Screw-ups in automation (i.e., failure to maintain the machinery properly) should be pretty easy to detect, and any company that's minimally concerned about its reputation would never ship a piece with manufacturing errors. It might be very hard to detect small changes in the formulation of the material, though. For example, I might find that there's a way save $ by mixing plastic in with my ebonite without any *apparent* loss in quality. If nobody notices, would you say I've lowered the quality? The flip side is that if word gets out about the change people will *assume* I've lowered the quality...