My response will be biased, because I'm a fan of Tunze products.
As Jauringer stated, the Streams will probably be too much for your tank. The smallest controllable model, the 6000, will probably cause turbulance and kick sand up in your tank, as the stream it produces tries to spread out to a 4'x2' space.
As a side note, I currently have a 65, which is the same dimensions of your tank, except 6" taller. I also have two 6000 Streams and a Multicontroller sitting in my closet awaiting a move and a 150 later this year. I've contemplated putting these on the 65 (dialed way back) as an experiment to see how they do in a 3' tank. I'll post something here in the Reef Tanks forum if I do, it's just I don't have the time to install them any time in the near future.
The Turbelle electronic powerheads would be a good choice for your tank, and are very underrated pieces of equipment with all the hype the streams have gotten. They still have all the controllable cabalities that the Streams have, except the flow isn't as spread out. The 7300/2 (up to 792gph) and 7400/2 (up to 1056gph) models both have 1" outlets that allow the flow to spread out much more than the tight, laminar flow of smaller powerheads; which is much better for your corals, especially non-sps.
Another option if you like the flow pattern created by the Streams is the Seio pump line. Seio has two pumps that create high capacity, wide flow patterns on the market now, one in the 600gph range and one in the 800gph range. They're inexpensive, but don't have any of the controllable capabilites of the Tunzes. Around here, Golfish and Skilos1 have experience with these pumps.
