Oh, Gun Scrubber is a great product and very useful on many common knives. But, it is a strong solvent and it can attack some plastics and other materials. So, you've got to be a bit careful.
Also, keep in mind that in the good old days, Gun Scrubber was basically a can of 1,1,1 TriChloroTriFloroEthane, the quintessential chloroflorocarbon.
Some time ago, we sent up a satellite which made, for the first time ever, measurments of the ozone layer. Guess what? There's a hole in the ozone layer over the south pole! The immediate conclusion was that that that hole was wrong and it must be caused by something we're doing. Someone then discovered that in a laboratory, chloroflorocarbons can destroy ozone. Eureka! Obviously, Chuck cleaning his knife with Gun Scrubber in Oregon, was causing a hole in the ozone layer over the south pole! So, that had to end.
As a result, Gun Scrubber, and a lot of other favorite products of mine, got a reformulation to elliminate the evil chloroflorocarbons.
Most manufacturers decided to try and make some good out of a bad situation, so they rebranded their products and "Environmentally friendly." Birchwood and Casey, the makers of Gun Scrubber decided not to change the product's appearance at all. As a result, many people are unaware that today's Gun Scrubber is a totally different chemical formula than that sold just a few years ago.
The new solvents used in today's Gun Scrubber are more agressive.
Benchmade used to recommend Gun Scrubber exclusively for all their knives. Then, I got one of the first cans of the new Gun Scrubber and watched helplessly as it dissolved the back spacer on one of my AFCKs. Benchmade withdrew their recommendation for Gun Scrubber promptly. I think they also changed the material used in that back spacer.
Anyway, just a word of advice: Today's Gun Scrubber is a great product, but it can attack some materials, so be a bit cautious with it around valuable knives with delicate materials.