I am on my second one of these tires, one of my sons stole my first one for a race, and then wouldn't give it back he liked it so much. In fact my 2 sons that race WEBE now use these tires, they are a fantastic value at a considerably lower price than the big guys.
My bike is an 03 XR250R, so this tire doesn't get the wear and tear that the CRF450Rs on the race bikes put on it, so for me it is a no brainer to spend $40 rather than $75-80 for a tire. Grip is great, even in the varied terrain here in the 4 corners. We have sand, hard pack, mud, rock, gravel, clay, you name it, and this tire works well on all of them.
The only complaints I have is this tire is a bit harder to mount than many tires I have used in the past, the bead is a true knuckle buster, even for a dirt bike tire. And the other complaint is one I've seen in the majority of Artrax tires, that is getting the bead to seat properly. Airing the tire up to even 50+ lbs. sometimes can't get it to seat completely, no matter how well you soap it up. But, even with those complaints I highly recommend this tire and other Artrax tires, they work great for trail riding and seem to work well and hold up for racing.