I've never used Kroil, and probably never will since it's not on a store shelf. I'm sure it's good stuff.

Hands down I will always use the 50/50 Acetone Trans fluid mix. I broke loose 11 45-year old brake line nuts without twisting the line. I can, and will, reuse all of them.

1972 Cuda 340 4 speed, 2001 Ram CTD 4x4 6 speed, 1970 Duster 408 4 speed, 1996 Ram 5.9 2x4 auto, 1965 Coronet 500