Ya, this is about whats happening to me as well with these settings.
Its actually not too horrible on my system for being in beta and unoptimized considering my computer is aging quickly. I get around 20-30fps when there are not a lot of units/action and it dips to 10 or lower for a few moments when the S hits the F.
Considering in DCS Blackshark I get those frame rates as well.
I'm using a AMD Phenom II 720 BE 3-core 2.8Ghz with the cpu unlocked to 4 cores running at 3.0Ghz, GTX 260 512mb, 4gig ram, Win XP.