On my 120 that houses two gigs, I have two MP40s and recently added a Gyre. After installing the Gyre I turned off the MP40s. I like the flow better as it is a wider, more gentle flow while still being strong. I only worry about long time reliability, so my plan is to keep the MP40s. I hear that many people run both, and I may do the same.
On my other tanks with smaller gigs (under 6"), I run WP10s and WP25s on wavemaking mode. They seem to like it as well. I'm guessing that smaller gigs have different flow requirements than the larger ones. I can't imagine putting my small gigs in the 120, as I think they'd get whipped around.