HAving run both tunze and vortechs, I can honestly say that I prefer the vortechs. I was very concerned about the inability to "aim" a vortech, but honestly, O dont see that it makes a difference. The flow is SO wide and dispersed. I ran 4 tunze that were just as, if not more powerful than the vortechs, and after running the vortechs, the amount of debris that was pulled out of caves, crevices, and nooks, was insane.
I, personally, think the nozzle on the tunze is too small and define, and still produces more a focused flow that the VTs, but they are still awesome. The new line have the Ball and socket mount, which allows for a lot more variability.
Nonetheless, I think flow is one of the most underated and overlooked aspects of aquarium health. Everyone knows that flows is best for "SPS", but I believe that overall aquarium health, including fish health, is significantly imporved with heavy flow.