I don't have an experience with the organization you linked, but if it is similar to Mensa, my advice would be: don't worry about anything, just go there and take the test. If they are a serious organization, the test will probably be very different from the online tests you took.

The IHIQS admission test actually is taken online for a fee of $5, in contrast to Mensa's which is taken in a controlled environment for a fee of $40, so I don't know how serious the IHIQS is. That's one of the reasons I was hoping someone here could share their experiences with them.

If you pass the test, there is a high probability you will be disappointed with the organization.

Yeah, that's kinda what I figured, but I thought I might as well see if the LW community knew anything about it.

You will find [in Mensa] also people who technically have high IQ, but otherwise are boring and/or irrational.

I'm sure I'd fit right in then. :)

My advice would be to pick the few individuals who seem better than the rest of the crowd, and focus on those individuals. Mensa can give you contact to these few cool people, but that's pretty much all it can do.

If networking with smart people is pretty much all Mensa's good for, could I just as well stick to LW?

Also, try the Mensa test.

I'm thinking about trying that. I wonder, though, if I should wait and try to practice for it, as the test batteries can only be taken once each. I would be very interested to hear more about your experience taking Mensa tests, even if you can only share general information about the tests themselves.