Been using both, the SLIP 2000 Gun Lubricant is a pretty good cleaner just by itself and except for the initial degunking of an old or extremely dirty gun, makes the Carbon Cutter almost unnecessary.
The bad news is it seems to evaporate and dry up much quicker than Breakfree and is a lot less effective as a lubricant once it does. I recently did a class and the action (AR15) would start slowing down by 400rds and start choking before 500rds if I did not add more lube. However, as long as you continue to add lube it will continue to run; but I've gone further using Breakfree.
Carbon Cutter is an extremely effective degreaser, better than Gun Scrubber at removing gunk and a lot easier to use in enclosed spaces and dispose of. Not to mention that it is plastic and wood friendly, so you can turn some cheap $3 tupperware from the grocery store into an instant parts washer.