Straight from the manual. This motor can't make 30lb-in at speed. The manual says the stock servos are 284 watts. Correct me if I'm wrong but the ac brushless servos make rated torque up to the rated rpm, with a flat torque curve like an induction motor, right? 400 watt ac servo may be a closer match to the original motors except for low speed and holding torque.
That said, I think I'm going with 750 watt servo motors on my boss.