with the flaming cliffs 2 there's a very involved mission builder toolkit update, along with new vehicle/helicopter models which look great in close up detail. add in the new aircraft models mods and it's a seriously impressive game-sim.
technical qualities of respective air-air missiles and avionics was painstakingly researched, references discussed at the ED site and is very well done considering inherent program limitations, Eagle Development went the full hog on that version, which is DCS Blackshark compatable in coop.
if you want real flight sim performance in a combat sim though, the DCS series (Blackshark, A-10), are the ones to get. If you want to fly Flankers and Eagles or Fulcrums then Lomac: FC2 is a must have, I can't go back to original Lomac now even though it's got the Crimea detailed with ground objects (FC2 changes it for detailing northern Georgia/South Ossetia). The aircraft/weapon characteristics are just so much better in FC2 and more accurate, especially the Russian radars, original Lomac was missing some data on their display, modes, etc. so it's more accurate in FC2.
Got some new weapons too, a bunch of other refinements, deleted ones that were never in reality equipped to forces, etc.