To do or not to do
It did seem to be on the high side. But he's having more than just the duals installed, and as long as its good quality work it might not be too bad. Shopping around is always good to do as well, but with a $300 dollar gift card... Maybe see if you can talk them down a bit!
Doesn't seem like it should take longer than that. I had a shop do my cat-back with tips on each side behind the tires with a 6.5 bed as well and took them only about an hour. That's with only one person working on it most of the time too





