I Use #9 on occasion but keep finding myself going back to what I used in Viet Nam, Still works great. Ever wonder when you see old pictures of soldiers in Viet Nam many have a green bottle in the attached to their helmet what it is? No it is not mosquito repellant... it is good old Break Free. We used it on everything from M16's to 85MM Mortars. Good Stuff for soaking, just remember to shake well before using, If you ever see some in a glass jar you would understamd.
Chief
I used to use nothing but Break Free about 20 years ago when I shot IPSIC and it worked great.
But I ran into a problem when I crossed over and used it on my safe queens and carry guns. (Autos only)
If the pistol sat for say 6 months or so untouched, the slide kind of froze up. The Break Free dried up into a hard laquer and glued the slides to the barrels. Cycling the slide did take quite a bit of effort, but then there was no lube, just hard laquer.
I have not touched the stuff since. ( I said laquer not liquer)
Now I know that this would not apply to Nam.
If I did try it again; I have won many bottles and cans of it at matches, I would be sure to work the actions weekly.
Just my experience.