Some of the best equipment I have ever used was at Powerhouse Gym in Atlanta. (Alpharetta actually)
I have never seen the brand around anywhere else and can't remember the name of it. But it was plate loaded machines similar to Hammer Strength but the difference was that they were designed to place additional emphasis/stress on the muscle being trained during the negative portion. It was awesome. You could load up a leg extension machine with 300 lbs and it would only feel like 150 lbs going up, but going down it was like an invisible man jumped on the pads.