Depending on the model, you can get decent low speed performance out of the Pullmor motor, but it will still have the speed variations on curves and grades without constant throttle adjustments.
If it's taking you to almost full throttle to get it moving, I'd be doing a tune-up on the motor and a full lube of the gearboxes and oiling axles. Of course, I'm assuming your track voltage is near 18V and you don't have significant voltage drops under load, that will make the AC motored units really bog down.
