I have Nattys Blue and Collinite 845 and I prefer Collinite. Whoever said Collinite is hard to take off is doing something wrong. Nattys Blue is MUCH harder to take off then Collinite. Nattys blue may look better, but the stuff only lasts like 6 days before you need to re-wax. Collinite lasts like 2 months here in the 100+ degree weather.
I like the Souveran over the KSG. Although, the wax does mute the KSG just a tad, it still looks amazing. However, a combo that I found to be absolutely amazing is the FK2180 anit-static sealant topped with Dodo Juice Double Wax which creates a slick "wet" looking finish.