2nd time for me with this tire, so no surprises.
Narrower than most knobbies, and taller too, so the bigger circumference changes the gearing somewhat.
The side wall has a step/shoulder at the rim to help prevent pinch flats, but that makes mounting a little more difficult.
The only way it could be better is if it mounted itself and lasted for 10k miles.
I put Scorpions on both front/rear of my 96' XR600r. I'm totally amazed how the Scorpions have converted my motocross bike onto a Sweet handling street machine. I take corners with so much confidence its "almost" scares me. Yet there's still plenty of traction for racing up/down the fire roads.
I replaced an IRC on the back of my Husqvarna te410 with the MT16 110/100x18 and have never found a weather condition or terrain that it will not work well in. I ride in hard pack clay and rocks as well as soft loamy rocky terrain and it very seldom loses traction.
The best tire for the money for off road woods ridding.
These come mounted on the new 690's... that should tell you something. I tried many combinations and brands on my 08 690E and the MT21's are hands down the best for DS. I have ridden the CDR and COBDR with these tires and would have no other. Plenty of miles left in a set after either of these treks. Some brands make the front end squirrely at high speed, but not the MT21. They are quite good on the road at any reasonable lean angle.
It is a good tire with a UHD tube, but it feels much better with the TUBliss insert. The full circumference support of the sidewall helps eliminate the tire roll through hard turns. Also, being able to run the tire at 10 psi (or less) really lets it soak up small objects in the trail.