yeah i got the black bottle spray stuff to. works good.
I do mine quite often, but i drive a lot. best thing to do, is just check it every oil change and see what it looks like. i get an oil change every month, so im checking it quite often.
during the summer i find i have to do it a lot more, thanks to all the dust and bugs. but late fall, winter, and early spring it doesnt need to be cleaned often.