Zeak,
I have loaded 90 grains of Goex triple F in my wife's Sidekick with no problem. It was loaded under a 245 grain Buffalo Ballet. About fives years ago I chanced to shooting triple F in all my black powder firearms. I did a lot of research and by talking to alot of old timers. I have found what the said is true. It's faster, less fouling and cleaner to shoot. I would not go with the maximum load posted with two F and would use 10 grains less than that maximum load for two F.
Good Luck!
Froghunter