@Andy.....I usually get 26-30 fps. Keep in mind though, I tend to avoid very dense areas and usually I'm flying over photoreal scenery. When I fly over Orbx scenery I get a drop in fps, but normally it doesn't drop below 21. I do however get the ol' "you're out of memory" error once in a while if I use a heavy aircraft such as the Carenado C340 with Orbx scenery.
I didn't mention before that I use Xtreme FSX booster and Game Booster. Also Bojote's tweaking and tuning tool is a very handy tool to optimize your performance.
Awesome work as usual. Were the Alaskan sceneries from Tongass Fjords?