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XOOPS itself works perfectly fine. Modules, that's a different story, but if the modules you are using are well supported and updated regularly, then you should be fine.
The only time I've had any problems with it is when I tried to run a 2.0.13.2 site with 2 + year old modules.
Insanity can be defined as "doing the same thing over and over and expecting different results."
Stupidity is not a crime. Therefore, you are free to go.