I have Tunze 6055 nano and 6100 Turbelle ; good pumps and i am very happy with my choice.
However if you have no controller to gavern all flow in your tank then go with Korallia save yourself some $$$.
For those who already have Nanostreams and want more flow you can easy modify them by cutting internal flow deflector tube "OFF".
http://www.reefcentral.com/forums/sh...highlight=6025
http://www.nano-reef.com/forums/lofi...p/t125770.html
I did not do it myself yet so i don't know if it works or not, but looks and sounds that it may work. If not this plastic part can be replaced.