I would go ahead and install X2 and X2a anyways, and the other guys are correct in that I don't think you are out any additional money to upgrade from X2 to X3.
I do not recall if there were any upgrades to any of the included components in X2, over what you have with 8.5.3, but you could use X2 to get up to speed on the major UI changes that X2 brought, and maybe by that time an X3 demo will be out there for you to evaluate.
Just make sure Windows is up to current maintenance levels, and your computer meets all other requirements for running X2/X3, and you should be fine.
I think it is allowable to buy X3 for yourself for the holidays - you've been good, RIGHT??? :)
Bob Bone