I love my 6" RC Lift. Paid $1400 for the 324S with Performance rear shocks from Amazon.
For the install shop to install the full kit, alignment, mount and balance rims/tires, and put my fender flares on, I walked out paying $1400 in labor. I believe he charged me $1000 flat for just the install. Can't be too sure. But yes, what you have been quoted sounds like a very fair price. Shop honored my worrying if the alignment was off when I went to drive it, re aligned it for free.
Also, I'm not sure if anyone else has had this issue with any other lifts.
I brought my truck back to the shop today because there is a squeak coming from the driver side rear axle. Guy seems to think the shock is rubbing against the top mount and is hoping the shock can be flipped around (rotation, not mounting point) to see if it has more clearance...we couldnt really see up there to see if it was rubbing without putting it on the lift. Gonna be bringing it in tomorrow morning first thing to have him check it out and I'll let you know what happens. So far this is the only issue I had with this lift and I'm just hoping its just a simple fix like the guy said. If not, Rough Country has a 3 year warranty on all components. So if the shock is bad, it will be replaced free of charge.
Anyway, those are my comments on the lift.