I'm alway a bit suspicious when a major company puts out a 'previously unreleased game' on its cheapie label, especially when, as in Spitfire's case, it turns out to be a game bought from Durell some time ago. So even Durell didn't consider it releasable? Let's see if my suspicions are confirmed...
Spitfire is set in the Second World War (take ten points if you guessed that, and six of the best with a broom handle if you didn't), and is a viewed-from-the-side dogfight game. It has a lot in common with those other Durell flying games like Deep Strike and Strike Force Harrier, but is most similar in gameplay to Again Again's Operation Hormuz, only with Spitfires instead of Harriers. (It's also a lot cheaper!) Lie that game it has air to air combat, this time against Messerschmitts and V-1's, and ground attack against lots of blow-uppy things, including something in the English Channel that looks like an aircraft carrier (but is probably a U-boat), airfields and a V-1 launch site in occupied France.
If you liked Operation Hormuz, and Snouty did when he reviewed it in March, then you'll probably enjoy this game too. I didn't.