I have both Fly! and FS2k2. I've always liked Fly! - the panels are gorgeous and the realism is wonderful. But the scenery downloads for Fly!2K were horrendeous to get, and I never knew quite what to do with them, so I didn't get them installed. (Perhaps you will encourage me to give it another try.) Somehow FS2K2 just worked, right out of the box, and has complete scenery around the world. It's much closer to Fly! in many ways than earlier versions of FS.
BTW, I take my hat off to Fly! for having a Mac version. MS has abandoned the Mac platform, atleast for FS. Shame on them.
William