As I work through my first bag from Layne I've come across several rats that are under the promised weight. I have a high quality kitchen scale that has never had problems and I've found rats as light as 15g in a bag meant to contain 20-29g feeders. Even if I assume the scale is off, which I don't since I weigh other commercial products that appear accurate, I would be surprised if my scale was off by this much.
Even visually, some of these are far too small to use as feeders for my animal.
So far, their response has been, to paraphrase, "we use an automatic sorter and we're sure it's right" which is both poor customer service and insulting.