I have only seen fantasmic once, with a dinner package. I have heard stories of people without the dinner package waiting in line for 2+hours to get the "best" seats.
For me, I think the mediocre seats, and waiting for 20-30 minutes is better than wasting two hours of my time. The show is great, but I just can't imagine that waiting for front row, center seats will make my vacation. My DBF used to wait in those seats with for his kids had never done the Fantasimic package until I reserved it...and he was apprehensive, as he had only ever sat front row center. From now on, he will always do the Fantasmic package, he rather spend the money then waste the time.