I only use brake cleaner to clean magazines.
It would probably be OK to use on a blued gun as is Gun Scrubber, but I wouldn't take the chance of ruining the bluing.
DO NOT get it on any wood or plastic grips. Don't even let a rag that has brake cleaner on it touch them, it will ruin them (ask me how I know
)
I get Brake Clean at work for a very good price, but it's not worth ruining the finish on a nice gun or grips.
I use Hoppes #9 on my Stainless and Blued guns, and CLP on my Nickel'd guns.
It's worth the extra $