The only safe place and use for the old-fashioned high-solvency type brake cleaners is on such things as trigger assemblies, and even then you need to make sure there's no plastic stop pins etc. Or thread locker / sealant on the set screws.
I'm pretty sure Tetra Clean is A-OK, but Google them, go to their website and either call them or send 'em an e-mail. Tetra Clean has an excellent rep!
I drop most auto pistol parts into a 2lb coffee can of low odor kerosene, the type used to burn in kerosene heaters. Not that it's a better solvent, but it just doesn't stink up my gunshop! Then I brush each part, wipe them down or spray with a commercial type of degreaser/cleaner I get from LPS Corporation, and then apply, VERY SPARINGLY, a slight spray of Rem Oil or Tetra-Tech or Break Free lube or LPS No. 2. Again sparingly. You don't want to attract lint, dust, etc.
Aside from doing an advanced cleaning of a leaded or coppered-up barrel, I can clean an auto pistol from stem to stern in about 8 min.
Good shooting! Hey Tin: my new SIG 556 will be here in about 10 days! Kid in a candy store, I tell yah! (check it out @ sigarms.com if I recall right.).
