I have a DC-12000 I've been using since January or so of this year when I built the sump for the 150. I've been pretty happy with it overall. I run it on setting 2 out of 5, which is supposed to be 70% load? When I bought it I was hoping to run it at least on 3, maybe 4, and I technically could turn it up to 3 if I made a few adjustments - but I found that setting 2 is plenty and my tank is staying cleaner than any tank I've had before. The kicker - I keep Japanese and English shubunkin - goldfish. Even with these messy fish the water stays crystal clean thanks to a 16 inch, 25 micron felt sock I use as the first thing water goes through in my sump. I change the sock once a week.
I am curious what kind if gph I am getting at 5 feet but I'm not too worried about it since it's been doing such a good job.