I had the Rhino Liner installed here in NJ. I was their first RL to be done there and they wanted more money but I talked them down in price. I just said to them, this is your first RL I don't want to be their guinnea pig. So they charged me $380 just to get the experience and I also told them I would mention them on the forumn. It took them the whole day just to do my RL and said they can usually do 3-4 trucks in a day. They said they would never do an RL again because the amount of time that is involved and the amount they should charge due to the time. They even asked me not to recommend RLs to them or to mention them on this forum.
Honestly, I think $600 would be a fair price considering what needs to be done. They have to remove all the panels, scratch the composite material, prime it, spray it ad put the panels back on. It's more work than most truck beds.
Pics of the liner here...
Rhino Liner Installed (Photos)