I'd like to get a 60" brush cutter, but my 743B only has 11GPM Aux flow and the brush cutters I see are 13-22 GPM required flow. While looking at specs http://www.bobcat.com/historical_specs/skid_steer/753_1990 I see the 753 is rated at 11GPM High Flow, while the 743B is 11GPM std Flow. Question is: How can 11GPM be High Flow? on one machine and standard flow on another?