I've used all of them, WipeOut is probably the best, but not by a lot different than the others which are all made by Milfoam, that's to include Hoppes, Gunslick, Outers and Forrest. They all work exceptionally well IF you use it properly, that's leave it in overnight and just use patches. The best buy on the Milfoam products comes in the Gunslick version at Sportsmans's Warehouse, 12oz for $11.
WipeOut is coming out in a new form called Patch-Out, not a foam, but a liquid, it should be available this spring.
Patch-OutTim
http://www.milfoam.fi/index.html