Lots of camos are effective when you sit still We play around Yellowknife, and ACU, Multicam, CADPAT, MARPAT, Woodland, DPM all work quite well when sitting still. Most guys often aren't noticed 'til they move, so the tan shouldn't be a problem. You can always spraypaint it something darker. I have an OD tactical vest that was too much of a contrast with my ACU, so I sprayed tan over it. A lot of the paint wore off, but what's left takes the edge off nicely (I'm soon getting a CIRAS in coyote brown, which we figure will work well without paint up here, and will be versatile with all the different cmos we use. I even use Desert MARPAT, and hide just fine.
Delenda Est Carthago