Summit or Jegs Exhaust kits
I installed the Summit full 2 1/2" exhaust kit on my Demon, behind a set of Summit headers. As mentioned above the quality of the kit seemed good, bends were good and the kit fit together well. The Drivers side went in without any problems. I would highly recommend trimming the exhaust pipe by 1" where it plugs into the exit side of the muffler (right before it goes over the axle). After doing this the exhaust pipe tucked in behind the frame rail perfectly, and it increased clearance around the axle by moving all of the pipe after the muffler towards the front of the car by about 1". At least this is how it fit my Demon...
The passenger side took a bit longer, mostly because I had to drill a mounting hole for the muffler hanger, and get a braket for the rear exhaust hanger.
The only other issue I have had is the passenger pipe gets a little too close to the driveline for my liking. But I am in the process of fixing that issue.
The summit kit also sounds pretty good. Not too loud but definately has a nice powertone.
Next step for me will be the X pipe kit.