adam96 -
The tuners that you mention in your post - Roe & Levin - and some others not mentioned - are all class acts and if I had unlimited funds...I'd have to flip a coin.
Other than Sean Roe's reputation, the things that sold me on his system were the affordability - both for the basic supercharger system and the fact that I wouldn't have to tear my engine apart to put in forged pistons. His twin screw supercharger also is perfect for my driving style of frolicking on the streets with no serious racing - the twin screw's torque - 603.5 @ 2800 rear wheel SAE corrected on my Viper lets me do serious accelleration on a regular basis (607.6 max torque @ 2950 RPM) without having to run up to the 6000 RPM redline, but if I do run up to maximum power at 5750 RPM, then I have 580.4 rear wheel SAE corrected HP. (I probably have even more power since the dyno run ended at 5750 RPM and the HP curve was still going up-up-up!)
Your Viper has forged pistons and you can go with Sean's Gen I Supercharger System when it comes out or with any of the others for a Gen I. Check out the differences in where the torque and HP are made from the different types of systems and what RPMs you normally drive at and also how you normally drive. See what system gives you the best power per affordable dollar for how
you drive. And then go get it!