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I won't get into better or worse (though, like you said, we are here so we probably like XOOPS better).
EXoops was a fork off of the XOOPS 1.3.X code base. The person who created the fork didn't like the inclusion of the Smarty cache that was introduced in XOOPS 2.
If you prefer the old code base, than you might like some of the things they've done with EXoops. But, I will tell you that the inclusion of the Smarty cache improves performance tremendously... giving you the power of a dynamic database-driven site with page creation speeds rivaling static HTML.
Also, it's not clear what the future development path for EXoops will be, while the community and development team here at XOOPS continue to expand.
In the end you need to choose which is better for you.
This thread goes into further detail:
What is exoops
