I bought 3 Sapphire 5850 Xtreme last week, and 2 of them i can get about 330Mh/s at 880/340 at stock volt stable, if i push the voltage to 1.25 i can get them to about 980 core and about ~400 Mh/s The other one is stable at 930/340 at stock volt (1.088) giving about 360 Mh/s and is able to give me almost 415 Mh/s when overvolted. The problem is that if i set the vcore to 1.25 it generates way too much heat and also the (electric) cost of running them supersedes the gain.
I did a transfer the 5th about 16.55 pm local time (Sweden) and i had the money available the day after. Was a very happy surprise as i thought it would take at least 4-5 days.