I have one now for about 2 months ( 150 ) I love it. I try to run 2 different settings if I remember to change them. Day time I run a 40% pulse at 10 sec. on off and at night 20 % forward and 80% reverse. Once in awhile I will give a good blast and run 80 to 100 for a few minutes to help clean out the bottom better but all in all a great unit Fish love it and so do the Corals. My bubble coral is crazy he will retract some when flow is down when pulse is on he will blow up and tentacles will come out and he's just rippling away. Great for giving the fish a work out, when i turn it up they will jump and swim in the current for a bit and then behind a rock and then back in. Out of any water movement device that I have used I have had the most positive results with the Gyre.
Another big plus is your Tank will be cleaner as it keeps particles suspended in the water and then of coarse your Corals will benefit that also. The one thing I would like to try is changing out one of the rotors for when in reverse it would have more flow so it would be 50/50 and see how that would work. I really can't think of negative thing to say. I have not tried it in the Vertical position. One unit, you don't really notice it and it moves a ton of water and dose it in a more gentle way then most of returns what more could you ask for. So from me 2 big toes and 2 thumbs up from me!
If your tank is under 5 feet I would look at the 130 and one other thing I thought of just know is your skimmer would probably work better to because the particles are suspended in the water column witch means better chance for them to go into your over flow and to your skimmer. If want to read a great review on these go to Advanced Reef Aquarist.
All the best.
Skim
I have never seen one in action in the flesh. Only videos. 