The SCT will tune the trans along with the engine. So you get better engine tuning (more power) and trans tuning (something most other tuners ignore). If you want the BEST for your 6.0, get a custom tuned SCT. Most here will recommend Innovatives tunes, although I've been hearing so good things about Cale's (from BTS) tuning.
AKBOUND - when / where are you bound in the GREAT state? I'm in Anchorage, grew up 14 miles north of Anchorage in Eagle River