I've heard a lot of both honestly. They are cheap for a reason some say, but at the same time others have had good luck with them. Depends really on your budget and what kind of power numbers you'd like to achieve. Reliability is also something you need to consider.
from what iv been told they are cheap because of there fitment, but if u have no problem getting hands on with the build then its a great kit .... Lots of people just run the kit and upgrade the turbo...
I will know more in a couple weeks when I finish my build. I should be ready to start putting the turbo on this week. I'm still finishing up my motor right now.
Most of their kits are pretty close to the same, just different brackets, and bends and piping sizes maybe. But otherwise just like the superchargers, everything else should be pretty much the same.