I have an EP-320 and the ez que with the 8" basket. I'm not crazy about it tho.
My main gripe is that the rotiss sits low. Not their fault, but the design as it is from weber makes whatever rotiss you use to sit real low. In order for it to fit, I have to remove the grates, and the three flavorizer bars in the middle. So then I am limited in what size trays I can fit down there to catch anything, and of course I have to foil the center burner to ensure nothing slips through and into it.
Again, not EZ-que's fault per se. Just not the best solution. I wish the rotis holes were higher on the hood. I'm jealous of grills where the rotisserie sits really high (which is also better as its further from the burners) and they can put any size tray right on the grates. I have to remove everything.