I'm installing headers on mine in the spring and will be getting an electric cutout myself - I'm going with Badlandz HPE. I just need to determine a location and tubing size before I order.

 

IMO, get a brand name with a good warranty. QTP used to be the popular brand, but with only a 90 day warranty now, I wouldn't touch it.

I believe the Badlanz is a 5 year warranty, and DMH is 4 years.

I've only got hands on experience with 2-
-I ran the DMH on my Grand Prix for about 8 years with zero issues. I cleaned it once in the first year of ownership, but never touched it again for the rest of its life. It was still working fine when the car got totalled, and was used at least once or twice a week.
-I've got a Jegs cutout on my monte now. I dont recall the warranty, but think it was rather short, but the unit was also pretty cheap at the time. I don't drive my monte a lot so I figured I'd try a cheap unit as it wouldn't be a big deal if it failed. So far so good after almost 2 years, but I've only operated it maybe 75-100 cycles in that time frame.

The big thing with a cutout is where you position it and what you do with the outlet. On my GP, I put a Y pipe in place of the resonator and attached it there dumping straight to the ground. Drone was pretty bad with the sound bouncing off the road and floor pan. Normal driving was fine, but long periods on the highway at a single rpm was annoying (luckily you can just close it).

 

I have used race ready on the first build with the monte. Then switched to a qtp on the other build. I also have qtp on our cts-v. All issue free and great units.

I never used dmh but heard there customer service department is garbage if you ever need to warranty anything.