I have used brake cleaner every time I cleaned them and then used denatured alcohol and then used rubbing alcohol. They have not broken down at all, holding 50+psi of boost without any failures for the last 6 months and 40Psi for a year before that and another 5 years of 30+psi of boost. I still use the stock boots at the intercooler tanks.
I guess I am one of the lucky ones.