You guys missed this thread.
I've been running this lamp since June.
http://www.canreef.com/vbulletin/showthread.php?t=25588
I run XM 10k's 250W on another tank, and the intensity is virtually indistinguishable. Not that XM's are no good, quite the opposite in fact, they're a great lamp and I'm a big fan of them. But as good as they are, the Iwasaki is just hands-down the best 175W lamp I've ever run. I regret selling my other 2 M57 ballasts now. I can't wait to see this lamp in other wattages.