I have 2 modded (Sureflow) Maxi1200's with the 2100
GPH prop and 2 Koralia 4's in my 125. With the mod the Maxi's put out a wider flow than stocl, but it's much stronger. The Koralias are strong with a wide flow. Add the magnet kit to the sureflow and it must cost more than a new Koralia, so for brand new I would go with the Koralia.
I'm thinking of getting the new models that can be used with a wavemaker.