Running just a wastegate can will deliver slow spoolup. I haven't tried a MBC but i did run on wastegate can only for about 2 years before buying the link and using it's boostcontrol. the difference in spoolup was amazing, due to the wastegate being held closed until either map is within 10kpa of target or usser set rpm is reached then wastegate is controlled by the user set duty cycle which should corrolate to the desired boost level. I have had people who used MBC's on mazdaspeeds that complain of overboosting in cold weather.