Lunner,
I have found in my SPS dominated display that the Vortech is the best for laminar flow at close ranges - I have corals about a foot from the direct flow of the pump and have no problems with dying tissue (tenius, steve elias blue stag, german green with blue polyps).
Conversely, on the other side of my tank, I have a Tunze 6000 blowing from the back left corner diagonally across the tank. 2 foot from that tunze I have 2 corals - a table and a blue ORA tortosa - both have lost flesh on the back side (the TUNZE blew the flesh right off) - the table ahs since reocvered and extending polyps like a furry kitten - the tort had to be cut down to a frag smaller than where the flow is - I am hoping when it grows, it naturally compensates for the strong flow of the tunze and grows heartier and thicker.
HTH
House