I'll just want to share my meet and greet experience with Steve Vai and Joe Satriani last year.
There were about twenty or thirty people in the group, almost everyone brought a guitar for Steve and Joe to sign. I was at the end of the line and have counted a JS, 3 Jems in the entire group and me holding my Universe. I noticed that whenever Steve Vai signs a Jem (while Satch is engaged in chatting with a participant), he would hold the guitar via the monkey grip, tap the headstock, then taps the body, then plucks the high b string. He did the same thing with my Universe. I was going to ask Steve about it but was not able to because Satch was really delighted to see the deluxe Chickenfoot III CD I brought for him to sign.
I think Vai is testing the consistency of the Jem builds. That's my guess (or maybe he always do it unconsciously). He has said it many times that his number one guitar "Evo", the body and neck resonates in unison. Unfortunately, I can't say that my Universe has the same unison tone. The good thing is, the Universe I have is not as bad as the two 7 string Prestige guitars I've owned previously. I've changed the pickups, used brass blocks and installed tremol-no units in these prestige guitars but they always lack character (sold them in the end).
Ibanez is not a bad guitar to play but it's extremely hard to get an exceptional sounding guitar out of the bunch.