For me, I only wanted to do this repair once.
I also looked at just replacing the o-rings, but at the time, 2 o-rings from BMW cost more than the bush which includes the 2 o-rings. Also, I am not sure what material spec the o-rings are or their durometer.
To answer your question... I have never seen the bush break. But think about this. It's a plastic part that gets heat cycled often much like the dreaded cooling system parts. So it cannot last forever. Also it's CHEAP. Current price is 7 bucks-ish from the dealer, too.
I understand about wanting to save money; I'm the same way. So if you want to save 3 bucks on a 2-3 hour job, that's on you. But I would not recommend it.