I'll show you slow! I did initial mowing at my place with a B7800 pulling a 5' RC (light duty one at that). 9'+ tall grass! These were paths and such from old logging activities. Tall grass is just plain slow to mow; one either uses a smaller mower and makes more passes at a higher speed or one goes with a larger mower and fewer passes but at a slower speed. I'm finding, however, in comparison to my 6' RC, that my 7' flail mows faster at a slightly slower travel speed when mowing 1' to 2' tall grass: less passes/turning and a wider cut more than offset the slower speed.I've found that the tall stuff really bogs my flail down, I have the betstco fh-agl165 with hammers. I have to move extremely slow or the 5-6' "swamp grass" as it's called around here will drag it down and smoke the belts. I've never cut this field, we've had the property for about 2 years and I only got the tractor about a month ago. My plan is to hit it earlier in the year and try to keep up with it.