I'm starting to think about my next move up. I currently have a 180 and I keep mostly softies and LPS. I'm running with my return pump directed in two direcitons (Mag 18) and a singe SEIO 1100. I was running two 1100s, but I found the flow to be too much. I know that sounds odd, being that the tank is a 180, but I found it made the parts around the powerheads unusabe for corals since the flow was so strong (and I'm not into SPS).
Anyhow, I'm thinking in my next tank (probably around 96x36x30) that I might try something like six SEIO 620s. I'm considering this for a few reasons. First, I'll get my flow directed from more than 2 or 3 directions (probably run one on each side and four on the back wall), second, the 620's are on the smaller side and third, the 620s are the most efficient SEIO pump - as efficient as a Tunze (77gph / watt).
Anyhow, that's my .02.
Ron