Personally, I like FAS better than BAS. ith FAS you get some very useful utility (the four 110v power outlets) and you still save a little gasoline. If you're using the truck as a mobile power plant, the exhaust is cleaner than what comes out of a worksite generator because the exhaust passes through a catalytic converter.

With BAS, you don't get the mobile power plant and you don't really save any more gasoline than with FAS.

The other thing I like about FAS is that it uses an integrated starter generator, not an alternator belt on steroids. I think FAS ill probably enjoy a longer service life than BAS. I also think FAS is more extensible than BAS. GM could easily release a "super power plant" version of FAS that could pack 144v like the HCH. You could have a whole lot of outlets in that configuration!