I've done both... Maverick is better. It's longer and more satisfying altogether. Fahrenheit is good, but there's not enough compared to Maverick, which does a lot more.
Fahrenheit was smoother with less headbanging, yet it also felt like the transitions were pulled out quite a bit and the ride didn't feel as overly intense as Maverick (mostly because it's lacking in the quick back and forth cornering that the latter is known for). The two drops are incredibly close to each other (and up there as two of my favorites), but I thought Maverick's was a little better since you came flying into it after the fast hill. By my list, Maverick is 11 and Fahrenheit 15, so it's not a big difference-- I just think Maverick has the advantage of doing more in the end.