I had a chubby 3 that shed 20-30 hairs each use,I didn't keep it long enough to see if it ever stopped,I sold it with the disclaimer at a loss...A Thater 30mm I bought used ,but only used a few times,shed the same amount for 2 dozen shaves,then all of a sudden stopped shedding...You never know....For sure,these big ,super dense knots can be shedders,but permanent shedding is reason for a return or exchange.You seem like you are well documented with Simpsons,and I believe after a few months if it continues to shed they will replace the brush for you.