I've had experience with a few tyres:
Continental Mountain King (I believe 2.3)- nice tyre, good grip, possibly needing a little more in the corners for aggressive riding.
Continental Cross King 2.25- an xc tyre, loss of traction on loose climbs and corners, worn out fairly quickly, a lot of noise on road, a basic xc tyre although.
Kenda Honey Badger 2.25- really light and less grip than the Cross Kings.
Maxxis High Roller 2 single compound 2.3- great tyre, my personal choice as there is no loss of grip, however a little chunky to push along sometimes.
Maxxis High Roller 2 Triple Compound 2.3- you can feel the difference from the single compound, they are just a bit softer in places which would probably help climbing. Worth the extra coin.
I generally run 30-40 psi as im not as experienced with running lower pressure and stick to the safe side as far as flats and buckled rims.