Someone was asking in a previous post if they help, hell yes they helped me. I ran 95 mph at Lake x with my standard bravo xr lowers. Swapped to the sportmaster lower, same length(we added 2 inch spacers) and ran almost the same speed but you better hold on for you life. The boat was all over the place. We skipped right over the 1 1/2 and 1 inch spacers and bolted the shortie right to the upper and man oh man, 102 mph. We did go up from a 32 pitch to a 34 pitch prop but the majority of that speed gain was due to the sportmaster lower and being able to raise the drives. With that extended skeg and the nose cone on the lower we really lost no control. Actually the comment was that the boat rode like it was on rails. So as someone who has done the testing on the sportmaster vs the standard lower, I would say it is worth a try. I would reccomend it highly but the guys at the lake said that unless you are going up with your x or you are already high, and running in the high eighties or above the sportmaster may actually slow you down becvause of the skeg and the extended nose cone.
I can not say enough about the sportmasters and Mike (goodfella) at Dollar Offshore. I probably asked him 1000 questions and he was always there to answer it for me.