yes, it's modded as seen here with add-on aircraft and the unified effects pack.
Vietnam was the first one I bought, along with the base pack. Enjoyed them so much that I bought all the rest the next month - and First Eagles 2 shortly thereafter.
FE2 is great fun - just like a cheap version of Rise of Flight - although it actually cost me more (I got RoF for £10 in the sale just prior to ICE being released
Also using the AG-XP Vietnam mod.
In the locked on aircraft screen above, you see the second Sidewinder hitting that aircraft (an F-100 drone in the 'Range' add-on). I'm sometimes finding I need three hits with the AIM-9 to bring an aircraft down.