Depends on what you're angling for.
If you're trying to stack Hold MAG beyond 54+ then the (perma) Dominator is going to be the superior choice. But if you're looking for sheer damage throughput potential, do not discount the value of Wormhole with KB>KD to enable "safe" uses of Fulcrum Shift so as to turn Impact boosted Propel into a single target "you die now, no waiting..." power on a Gravity/Kinetics Controller.
Dominator can stack deeper MAG.
Controller is more versatile, depending on secondary powerset (and with Kinetics can get rather brutal via buffing).
So it depends on what you're (really) angling towards wanting to play.