My 2 monarchs have been doing awesome pumping out 1.4 Th/s for over 3 months without any problems, and if you're having any "failed to find work for queue results" it's because you're using the wrong app. Get the one directly from BFL, a custom build for monarch, which will maximize your hash rate and get rid of that error, you can get it here: http://www.butterflylabs.com/drivers/bfgminer/