Graphically the old girl's past it, but as you say... nothing else can immerse you quite the same.
Black Shark trumps F4 in terms of switchology I suppose, but for immersion it sucks terribly. In F4 you can hear other packages in the fight "Cowboy 12 defensive..." etc and the occasional "bollocks!" which always gets a giggle.
The way SAM's talk to each other and pop up right in front of you like PEEK-A-BOO IM HERE! *que missile launch tone*
I remember the first time I got engaged by a missile I nearly jumped out of my seat! BWABOOBWABOO BEEP BEEP BEEP BEEP BEEP BEEP BEEP!!!!! "OH F**K!"
Good time's indeed... I just hope when DCS:Warthog comes out they've brought the environmental immersion in a bit more otherwise it will just be another case of lots of buttons and an awesome aircraft to fly but the outside world is pretty much dead.