Yes...but...
We did two Fantasmic dinner packages. On Memorial Day we ate at Brown Derby and Fantasmic was rained out. Saturday we ate at Mama Melroses and got to see Fantasmic (in light rain.) BUT, for 5 of us (3 adults and 2 kids, one alcoholic drink) the tab with tip was $150.
The reserved seats are the two far right hand sections. The seats are good BUt when we arrived at 8:15 both nights, the corresponding sections on the far left were almost totally empty. You could get a seat as good as what we had at 8:25! With that said, we got our seats without waiting in line at all.
If you had planned to have a nice sit down meal all along, go for it. Otherwise, it's a lot of money and the show can be cancelled.