Of course, it all depends on your family, what you like, how busy it is, etc., but we went to DQ last September, and we don't have any plans for going back again. It does feel cramped, strange to navigate, and the one "special" game that we played (the rafting game) seemed like you were paddling for nothing (I couldn't tell that my actions were making any difference).
I can use WinMAME on my PC to play all of the old arcade games (burger time, pac man, Golden Axe, etc.). When I'm at DISNEY WORLD, why would I really care to spend several hours of my time in a dingy, stinky, dark arcade when I could be out riding a ride or even just checking out another resort or something?
I doubt that I will change anybody's plans for going to DQ (just PLEASE tell me that you're using one of many "Water Park Fun and More" options to go and NOT paying 'full price'), but at least you can say that I warned you after you go. I thought it would be fun to try, so we did it on our last day last year. We were out of park admissions (except for the water park fun and more), and didn't have a lot of time to do other things. So, it wasn't a big deal for us to go, but--given the chance now--I'd take that time back and shop a little more or visit another resort or something...
Sorry, but I just don't have anything good to say about Disney Quest...