Full frame is not everything. its not going to make ur photo taking skills increase 10 fold, or ur photo will have even more wow factor.
if u r not sure, can always have hands-on by renting it.
ask urself, why u need full frame? do u really need full frame? if u don't need or have no idea why u even need one...of course its not worth it. but if u got the cash, just go for it , buy and take more photos.