I did their FT clone as my very first brew. Used the LME version with the WhiteLabs liquid yeast they recommend (think it was 001,without looking it up) - no starter. Not knowing any better, I followed the recipe exactly... And definitely got that sweet extract twang from not doing late LME boil additions. Also didn't get it chilled down as quick as I was hoping (ice bath), and it does have some cloudy chill haze. And i fermented it at room temp in a closet (for the times they said - one week primary, one week secondary). BUT, that being said, I still think it tastes good, and even had SWMBO and some friends say they liked it better than the original (when compared side by side. They're not beer people really, though, so they prob liked it being a bit sweeter; or they were just being polite!).
I'm wanting to try it again, now that I have better knowledge and techniques and (almost - will before I brew again) a fermentation chamber. I am saving the last six pack to compare with it when i do.
Anyway, I'm sure if you have good techniques/abilities already, you'll make the AHS Fat Tire clone into a great brew!