I bought my turbonetics kit used and got screwed on some pipes that were damaged. I can say this, turbonetics is awesome to deal with, they are a big help and very easy to work with and I bought the kit second hand. The hellion kit uses turbonetics components, the kit is less expensive but I am not sure why. I know bassani makes all the hot side piping for the turbonetics I am not sure who does for hellion. Considering I just did my install, my advice to you is do your research, don't buy used because you will end up with ordering parts that are missing or broken like I did. I am VERY happy with the turbonetics kit, the kit isn't bad to install. If you have any questions pm me. Also I did bbk tuned ceramic shorty headers, high flow cats and motion delete plates, believe me the power comes on quick, there is plenty of low end power all the way to red line, its amazing to drive and sound incredible. I also added a boosta pump, diablo mafia, and a in cabin variable boost controller, check my post under multimedia 'OH OH its MAGIC" There is 2 video clips too. Let me know if you need anything- Rob