Just found out that FO3 and FO:NV are on sale (with all DLC) for $5 each. I have both on 360 (and have all the achievements in FO3), but it would be nice to play with mods.
Trust me, take the opportunity. I had New Vegas on my PC for a time with all the DLC (bought it on 360 as well), and while I had to drop it because it didn't run well enough all the time to justify it taking up so much space, the mods totally changed the experience. I had several large quest lines added, a ton of weapons, armor, and items, an extremely in-depth needs mod (which actually tracks things like malnourishment due to lack of protein or vitamins/minerals, water poisoning, and the faster dehydration due to large consumption of fluids leading to excess urination), a ton of new handloading recipes for my guns, a lot of workbench recipes for making just about any item in the game (with added resources like steel, brass, ceramics, and electronics available for a more in depth crafting and deconstructing system)....
Basically, I turned the game on its head and made it into something far larger than its creators ever could have done.