I tested out the Five Fingers on Flattop today for the second time. I ran up the backside on the "runner's trail" and posted a decent early season time. The weather was stellar and the temperature was warm enough to run only in shorts. The Five Fingers made the minimalist style complete. Feeling the warm rock and soaking up the sun's energy like a sponge - this has got to be barefoot mountain running in Alaska at its finest.
Without intending to sound like a Five Fingers apostle, I must say that if you're at all inclined to try out barefoot running or some sort of minimalist shoe style, I really like Five Fingers. The backside of Flattop is no problem at all and although I haven't tried the Five Fingers on Peak 3 I'm sure it would be fine since I made it up and down that peak last summer completely barefoot. Peak 3 has even less gravel and rock than Flattop.
I hope you're out enjoying the weather.