You could also look at VMP tuning, TBH I also like Lund tuning as well. If I could offer but tuners I would
We currently have a 850hp 07 GT500 tuned by VMP, my Boss is tuned by VMP but John Wyatt (JJ on Hypermotive) has his Roush blow 12 tuned by Lund and is pushing right over 600.... safely on 93 octane.