The X-Wing Alliance Upgrade Project is a graphical update to the Lucasarts flight sim X-Wing Alliance. This, combined with other mods, will allow you to play through X-Wing, Tie Fighter, X-wing Vs. Tie Fighter, and X-wing Alliance with upgraded graphics, and improved gameplay mechanics. Other customized missions can be found onder the "addon" section.
The bottom one was done by Matt, and the top one was done by Tottally Games.
I actually kinda prefer the original design, actually.
The one shown above the xwaup one or the one from the MS-DOS Versions of TIE Fighter? The bottom one is based on the latter.
I prefer X-Wing Alliance's version with the more square design. I don't even remember this class of vessel in Tie Fighter, granted it's been ages since I played...
The new design is quite well done, however...
The old design fits the Empire better with it's boxy, no nonsense utilitarianism look. The new design seems like it would be out of place, and would fit another faction better.
Actually, looks like something that a bounty hunter would use.
The custom one is acutally based on the very first appearance of the DOS version TIE fighter.
The 1998 Windows version one looks a bit like a Lambda class Shuttle.