I'm using these calipers with Shimano XT levers, and I'm happy so far(3 months of use). 4pot infront, 2pot rear. I use original BS05 shimano pads for rear brake and COOMA pink (ceramic) infront.
Resing BS05 pads bites earlier and have less modulation than pink cearamic. Overall, i think this calipers are good for XC. The levers are ergonomically and aesthetically bad, i dont like them at all.