OK, just want a little feedback. I have a MT43 on my Beta 300 and it works great with low pressure and the tubliss set up around here, Walker etc, but planning to ride Mattawa soon and want to spoon on a Dunlop AT81 desert for some added knobby fun. My problem is what size. 110/100 18 or 120/90 18. Which would you prefer and why.