I've stuck with Kenda tires so far. The Small Block Eight is a fast rolling tire, but has less traction for cornering or climbing out of the saddle, and clogs with mud easily. The Nevegal is slower rolling but has huge traction and resists mud sticking. The Karma is a nice compromise in speed, traction and mud performance between those extremes.
My tires closely resemble the Conti Mountain King above, they are Michelin. I chose those because I do ride on the road to get to Beverly, I originally bought them for sugar bottom, and loved them there. Rolling resistance is low with good control. The only thing I didn't like, was when new trails are built at Beverly, I got more flats, I think from all the open space in between the blocks allowed the little sticks in the ground to poke through easier, I have not had that problem in the last year.
I'm currently riding Bontrager XDX's on my bike and have been pretty impressed with the low rolling resistance. They are a lower profile tread, but I haven't had any traction issues since I run tubeless.
My favorites so far have been Maxxis Ignitors. I am currently running Rocket Rons, but I am thinking about putting a quicker rolling tire on the back like a Small block 8 or Racing Ralph. One thing about our trails is that big knobs are not needed IMO.
i forget what my 06 hardrock pro came with but since i rode mainly concrete and tar at the time they didnt last all that long. when they were done i replaced them with specialized hemisphere armadillo. mainly due to what i was riding and i wanted alot less rolling resistance. they have worked great for that and have lasted alot longer and still have alot of life left in them. however i noticed the last time i was out at Beverly with NoyzSource i definitely didnt have a tire for there. in fact the treads are still packed with mud and in some spots i felt i was losing grip. granted i dont have the seat time alot of you do, but i dont think they are suited for Beverly. i havent had this issue, but here is the tire i have http://outsideforever.com/gear-reviews/ ... ycle-tire/
i am definitely going to take note of what others use and see about getting me some new tires