I have a hydor koralia 3 and also a tunze 6045 in my 80 gallon. The hydor koralia is rated at 850gph and the tunze at over 1100gph but in terms of visible water displacement the Koralia seems to push about the same as the higher rated tunze.
They are setup on opposite sides pointing at each other and turbulence hits right in the middle of the tank. I've been happy with my hydor koralia so far, it's very quiet and has a nice mounting system, also I paid half as much for the hydor koralia ($44) as I did for the 6045. One advantage of the tunze nano stream lines is that they are smaller than the hydor koralia, but I think this would only be a factor in a very small tank. Both are relatively small and not an eyesore in my 80g.
Stream type powerheads are the way to go. Vastly lower energy consumption than the traditional powerheads with more gentle and uniform water displacement.