Not coolest, but Recon Phantom feels the best when used IMO. Some skins just makes guns feel like shit IMO like all the slim Phantom skins like Protocol, Ruination etc. but skins like Recon Phantom what makes the gun more bulky make it feel better.
I wasted 20euros for Protocol and hating using it due to it feeling slim to be. Makes it really uncomfortable to use. Recon has bulky design and even hand grip that makes it feel even more stable.