I have the large Stirling badger brush (butterscotch-colored handle) and one of the boar brushes. The badger has yet to lose any bristles so far as I can tell, and it's been my go-to brush since I purchased it last year. The boar, on the other hand, sheds a few bristles with every use and many seem broken. That's a shame because I am definitely a Stirling fan and I hate to have wasted the ten dollars plus shipping and handling on the boar.
Oh yes. I soak my brushes while I'm in the shower, so they have plenty of time to absorb water. My Omega boar sheds the occasional bristle, but doesn't do what this Stirling does. Could be a dud, but for ten bucks, I'm reluctant to ask for a replacement.