When comparing Just Cause (1-3) vs Fallout: New Vegas, the Slant community recommends Fallout: New Vegas for most people. In the question“What are the best shooters on PC for people who don't like shooters?” Fallout: New Vegas is ranked 1st while Just Cause (1-3) is ranked 4th.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Run 'n Gun gameplay
JC is less of a traditional shooter - rather than acting like a soldier, you're encouraged to be a "Jason Bourne" style action hero. While shooting is a huge part of the game, it also focusses on being able to run around freely, hijack vehicles, paraglide/grapple-hook between buildings, and blow up everything.
Pro Huge map
Cons
Con Only runs on Windows
The lack of support for Linux means you'll need a separate Windows box just for playing the game, and sadly Virtualbox doesn't have the performance to handle it.