oh i forgot, the Destroyers there are great fun - better have a lot of time to spare though, Sea War and Land War is on a different level to Aces High; but they are entirely different games. I cannot play WWIIOL for very long without getting extremely bored, AH can keep me going for hours on end.
The historical gunsights and bombsights are quite good too, in blenheim you have to look at the dials, check speed/alt, calibrate using the two sliders and watch as they adjust the aiming point. The range settings on the german tank sights (and later allied types) is good, graphics are superb too - i absolutely love it when you nail a tank and the turret comes off, or pop an 88 into some poor little frenchy's head and all you see is a red/black smoke puff.
The ideal game would be a combination of Aces High air war and WWIIOL ground/ship war (although the choice in wiiol for boats is limited to a fishing boat, freighter or DD).
