I too am trying to decide which power adder is right for my 12 GT.
I have had centrifugals, positive displacement superchargers, I've got a turbo Dakota 408, and had a few nitrous
equipped cars too.
I have been leaning towards the stage 2 VMP kit but everyone running the Paxton kit impresses me with how they like it, ease of install, and power.
I'm still about 12 Mo out on purchasing a boost device so I have some more time to save and research...
Good luck, let us know how it goes?