I have had a dc12000 running for a bit now and my impressions are the following:
pros:
-very powerful
-1.5" in and out allows for hooking up proper sized plumbing and not losing head by reducing right out of the gate.
-soft start ramps up after power loss or when coming back from feed mode.
-feed mode @ 10min
-control chip in controller (not the pump) which will allow for modding pump to be controlled by reef angel/apex/ect..
-value for the cost is great.
cons:
there is a hum which was mostly eliminated when i unattached return to aquarium from the wall it was vibrating against. But is louder then the RLSS dc5000 it replaced (not sure how it would compare to other pumps of similar size as i have always ran a dc5000). But there is definitely a hum that i am ok with but may not be ok for someone with a dead silent system.
I have had a few requests for a picture of the control box open so people can figure out how to mod for full control. So here it is:
