I have read several stories about brushes deteriorating rapidly, hair falling out, knot separating from handle, and other disasters. I wonder what kind of warranty is provided for the various brush brands fellow forum visitors have purchased. I just ordered the Merkur Vision set which includes a Brush with a brass handle, 22mm Silvertip knot (The brush can be purchased separately for $80 at West Coast Shaving). One good point for this brush from Merkur is that it comes with a 10 year warranty. That gives me some piece of mind...
I think the one I got from Amazon (a Tweezerman badger-hair) came with a 10-year warranty, but I honestly don't care. It was $12, and if it collapses, hopefully I'll be in the financial shape to get a better one! Also, for $12, the amount of time and energy to get a replacement is probably not worth it.
Warranty on a cheap brush is not important but it may matter in a $100+ brush! I agree with your judgement. A $12 brush is almost in the disposable range (cost wise, no quality judgment intended!). I launched this thread thinking mostly of the very expensive brushes I see discussed in the forum. When you spend over $100 and over $200 for a brush you may pay more attention to what kind of support you'll receive for that large expenditure.
To be honest i have never heard of a warranty for shaving brushes. I do know that most reputable sellers will replace / refund for any unused brush. vulfix/Simpsons will replace a shedder with out hesitation.
Brush manufacturers should disclose their warranty terms When you spend more than $50 for a shaving brush I think you are entitled to know what kind of warranty you'll get. It's good to know that vulfix/Simpson stand behind their product. I understand Merkur is very good too (or so I hope) with customer service and warranty repair/replacement.