It's hard to compare racks. But I've been using ROS racks under my entire system. I would say that the design lean towards lively, dynamic, and open sounding, especially if utilizing the "spring" upgrades to the reference level.
All their footers, feet of silence and discs of silence, tend to sound that way as well. The older version of the rack utilize ball bearings (comes standard) underneath components. You can buy wooden pucks to sit on the beams and use SolidTech footers or any other aftermarket footers. The current version got rid of the ball bearings and use a more stable system to hold components. They also use spikes at the bottom of the rack. I don't know if there's any difference in sound.
One thing to know is that the spring-loading (reference upgrade) can only be done to the middle racks, the top and bottom shelves need to be fixed to keep the rack rigid. My TT, a Michell Orbe SE, sits on top of an IKEA chopping board, then on a set of "bench cookies" onto the top shelf. The TT itself is spring-loaded. I can say that at minimum, the rack does what the company claims. My kids like to run in and out of the room, and I never had the stylus jumped. That's. of course, before I loaded them with sugar...
FrankC