I take quite a few non-flyers flying and I always get a reaction:
generally it is - wow, I now know why you love it so much, what an experience, that upside down stuff is so weird!
or occassionally, "I'm really glad that we did it but next time take my sister".
I do have two rules and although generous with my invites (I pay) I assess the suitability of the pax before I offer. The second rule is that those that I have invited are given 3 opportunities to come flying. If they've turned down 3 trips because of personal circumstances, then they really weren't that keen at all!
Stik