Probably overboard for the usual player, but I use a Thrustmaster Warthog. I do fly more "real" sims.
Since using it in ArmA2, my control has grown by leaps and bounds.
I used a Saitek in the first ArmA, which worked fine.
Back in the OFP days, I always felt a "disconnect" using a stick, and it never felt natural. Mouse and keyboard worked fine for me there.