I'm not sure if it is the high useism, or something else, but I am having issues getting much past DRMI. I was able to make it past the CARM reduction one time, but since then I have been struggling with getting a stable DRMI. With DRMI locked, POP18 and POP90 have large, ~0.1Hz, period to them. This seems suspicious of the useism, but I cannot say for sure.