I have seen that "silly putty" stuff advertised gh-pp, not used it yet, but interested in seeing if it is a good option.
I personally clean by tipping up, I don't eat over my gaming keyboard but crumbs and stuff seem to get in there, (odd). I will see a difference when my new board arrives as that has a plastic cover which I will make use of when not using the board.
Every month or so I go to town with a brush and air duster, and my keyboards have lasted years.