I have the latest version. Don't think I ever noticed so much because I mostly played QMB and LAN. Years ago when I last played campaigns, I only flew IL-2s and don't remember it ever being an issue. Now, with the B25, He-111 and Hurricane campaigns, it's very noticable. I'm aware sharp stick movements will slow me down and I've been using the trim to climb steadily rather than in spurts, but I still lag. Would be nice if they weren't so ruthlessly efficient or their cruising speed was reduced just a touch. Then I wouldn't have to be the flight leader.
Part of the reason might be I'm seperated from my stick and peddles at the moment and using an old thustmaster gamepad. It's dual analog, and I assigned trim controls to the D-pad. Of course, it's no substitute for a stick.