I have a Maxxis Crossmark on the rear. Sucked to mount (I run Stan's Arch EX rims), sucks in mud, sucks in powdery dust or sand, weak side walls. Positives are high volume and fairly cushy (due to the weak side walls I suspect) for size. Otherwise meh. This is a race tire for World Cup courses I guess. And it is pretty fast for a tire with actual knobs.
I run a Kenda Karma in the front. Pretty much the same characteristics except I was able to keep all my fingernails mounting it, but it is impossible to run tubeless. The carcass leaks and leaks and leaks. When the carcass stops leaking that just means you're out of goop and you should expect the tire to be flat in the morning.
But I'm a stubborn butthead, I don't run actual tubeless tires, too heavy, you know, on account of having enough rubber not to leak air. :-)
'91 Pickup - Imelda
'08 Tacoma TRD - Donna
'09 Kawasaki KLR650
'12 Gunnar Rockhound 29
"Our task must be to free ourselves from this prison by widening our circle of compassion to embrace all living creatures and the whole of nature in its beauty. Nobody is able to achieve this completely, but the striving for such achievement is in itself a part of the liberation and a foundation for inner security. " --Albert Einstein