The mig-range was much better after I drilled the baffles and before I went from 10% to 30% nitro. It ran way to rich at part throttle and the high end just didnt seem right to the ear if you know what I mean. Once the 72 lost all that back pressure it really came alive and as much as it improved then, adding nitro just made great things even better. Now the 72 swinging a Zinger Pro 12-6 can just about hover my 6Lb 10oz GP CAP 580, almost.