I usualy go heavy with helicopters and people who have played against me at least once know that and are always ready with heavy air defences. I still don't see a particular problem with using fixed wing craft. I play modern battles almost exclusively. I just always make sure I use heavy SEAD missions who even if they don't destroy/disable SAMs, they do manage to draw several missiles to them, with some UAVs as an additional force, most of the dangerous air defences are, in one way or the other, neutralised, and the Strike crafts are more or less unopposed to do their work.
Considering I play as Greece which doesn't have some of the planes of major powers, and still manage to use them, it leads me to believe that perhaps you guys are not following the right tactics, or just are very unlucky.
If for example I only sent strike aircraft without any preparation, I don't know how many of them would make it to a second run. I realise that perhaps buying an expensive SEAD element (or of course more than a couple) might be seen as waste of money, but unless you go with 20+ stike crafts in the same turn, I don't see fixed wing craft working that well against a good opponent.
Just work more on it, but don't expect miracles. They can't win a battle on their own.
And if anyone wants to try it, please check this thread
http://forum.shrapnelgames.com/showthread.php?t=42821 (wink wink)