The price on Trevor's kit is just the springs and the alignment cams. Shocks aren't included on that. The Icon kits on Truck Toyz come 2 different ways, 1)Coils, cams and shocks for 825 or 2)Coils, cams, shocks, rear blocks and U-bolts for $1050.
Neither of those kits include a solution for the trac bar, so don't forget about handling that too.
Trevor's coils are Icon coils, I'm not sure why he's not advertising that on his site, other than Icon is kinda his competition, but I'm sure he's got other good reasoning.
It's really just a judgement call on you're part. Icon shocks are about 110 if you buy them outright(at least mine were) so you're probably going to end up spending about the same amount.