These opt's where created for the X-Wing Alliance Upgrade project in a attempt to visually enhance the craft in the X-Wing: Alliance game.
Though you can download them here, you can also download them from XWAUP.

Incom Corporation T-65 A2 X-Wing Fighter 25th Anniversary Edition v4

The Rebel Alliance's X-wing starfighter was one of the most advanced fighters of its day when Luke Skywalker flew it into battle against the first Death Star. Many fighters have come along which are faster and more heavily armed, but the X-wing has been assured its place in history because of its role in that stunning Alliance victory.

Yet it's a miracle that the Alliance has the fighter at all. The T-65 X-wing was the last starfighter design produced by Incom Corporation before its seizure by the Empire. When the X-wing was in its final design stages, ISB (Imperial Security Bureau) agents began to suspect that members of Incom's design staff might have sympathies for the Rebel Alliance. A Rebel Commando team helped Incom's senior design staff defect to the Alliance; the designers took with them all the plans and prototypes of the X-wing.

Update v4: Due to some incompatibility issues when installing the Arc-170, previously to installing the X-Wing, the game crashed, this update fixes that problem.

Koensayr BTL-A4 Y-Wing Attack Starfighter v2

The Y-wing is an older design, predating the X-wing and TIE/ln by Several years. These fighters have a reputation for durability, and are in use at countless Rebel bases. Their limitations were made abundantly clear at the Battle Of Yavin: only one fighter from Gold Squadron survived the battle. Its distinctive narrow central hull section easily recognizes the Y-wing with its two large engines set far away from the body.

Before the superior X-wing was introduced, Y-wings were the flagship fighters of the Rebel Alliance. They played a prominent role in the Battle of Vnus at Duro and the First Battle of Ord Biniir. Rebel Alliance Y-wings saved thousands of lives by holding off Imperial TIE bombers during the Siege of Ank Ki'Shor. Two squadrons of Y-wings were used at the Battle of Yavin, where the first Death Star was destroyed. As the Alliance gets more X-wings, Y-wing fighters are increasingly being shifted to outlying Rebel locations, and are more often being used for raids on Imperial convoys, rather than engagements with TIE fighters.

Dodonna/Blissex RZ-1 A-Wing Interceptor v4

The A-wing was the fastest starfighter in the galaxy at the time of the Battle of Endor. Designed by Alliance General Jan Dodonna and Rebel engineer Walex Blissex, the A-wing was intended to be a high-speed ship capable of outrunning anything in the Imperial Navy. At the battle, a single A-wing destroyed the Super Star Destroyer Executor when pilot Arvel Crynyd rammed the Executors bridge, causing the ship to crash into the Death Star.

The small, wedge-shaped ship continues to be the Alliance's main interceptor fighter. It is an exceptionally difficult ship to fly because it is constantly pushing the limits of performance. The A-wing is constantly subjected to incredible stresses, and its engines, hull, and weapons systems require constant maintenance. Since it is only 9.6 meters long, each ship component is wedged into the cramped hull, and even the lightest hit can cause critical system failures. The pilot is almost totally exposed to enemy fire.

What's New about it?

The A-wing Version 3 now comes with an improved cockpit interior, new pilot, and engines, all three opt have enhances textures making them slightly sharper.
The Base opt now has a LOD Opt.

Slayn & Korpil B-Wing Fighter v3

The B-wing was the Rebel Alliance's most powerful heavy-assault starfighter. It was designed to take on much larger Imperial capital ships, thus providing the Alliance fighters with the punch of capital ships at a fraction of the cost Although only about four meters longer than the famed X-wing, the B-wing had more firepower than many Imperial patrol ships. The B-wing starfighter was designed by then Commander Ackbar with the help of engineers from the Verpine Slayn and Korpil colonies.

The B-wing is essentially a long, flat wing with a cockpit on one end. Two folding airfoils near the midpoint of the primary wing extend out for combat. The fighter has an unusual cockpit gyro-stabilization system that allows the cockpit to remain stable while the rest of the ship rotates around it, significantly reducing stresses that result from sudden manoeuvres. Unfortunately, this complex gyro stabilizing system frequently breaks down. This locks the wing assembly in position, making it almost impossible to turn the ship without severely straining the spaceframe.

What's New about it?

The B-wing Version 2 has been totally resized; the hull textures have had a slight makeover making them sharper in appearance.
The main changes are to the cockpit pod, due to the limitations of Ace Dxf's rotational application at the time the first B-wing was made the cockpit pod was in one mesh, but with the advancements made with OPTech, manually editing the rotational axis's, I was able to split the pod in to several different meshes, enabling me to add more detail to each part.
Like I said the main changes where to the cockpit, this includes the B-wing Cockpit Opt, I have totally remade this, adding more detail i.e. levers, chair (By Sergione), screens and so on, scraping the old textures and making totally new ones.
The Base opt now has a LOD Opt.

Explanation of LOD or (Level Of Detail), a LOD is a low-resolution (low faced count) opt incorporated into a high-resolution (high face count) opt. From a predetermined distance the opt reverts to the low resolution model to speed the game play, the closer you come to the model it reverts back to the high resolution model. For other information please read the Known Bugs report.