The Vertex has a larger capacity and uses larger fittings (1/2" vs 3/8") so you can run more flow through the pellets to keep them tumbling.
I use a phosban 150 and it works fine. So people have had issues will getting the pellets to tumble in a phosban using a powerhead but my Eheim 1260 blasts through flow without issue.
This reactor is the ultimate pellet reactor (and absolutely beautiful to look at as well):
http://www.marinedepot.com/NextReef_...FRISCR-vi.html