I've been using SEM Sure Coat (not Color Coat) in recent years. Before that I used ColorPlus which is basically the same product as Leatherique. The two companies were formed in a dispute in the estate of the original inventor. I think all 3 are fine. SEM is a real full line auto chemical company. The other two are small family owned companies with likey more personal service. I think they are all similar material - an elasomeric, polymeric water based surface coating. They adhere well and wear well. SEM is cheaper but has fewer colors and most need to be mixed (except black/white/silver). They also have many dealers who can mix colors, usually for a color match charge. With SEM I have always put it on with a 3 inch cloth paint roller which works fine, arguable better than spraying, and certainly better than brush. It's water based, clean up is easy, etc. I've never done a complete color change but it's really quite easy to do. With roller I think you could do an entire car with 2 quarts, under $100. To really do it right you need to take the seats out, and maybe the door panels off and get it all very clean.

http://www.sem.ws/index.php