I'd be curious about the ways in which different amp stands effect amp sound. That they differ in appearance and cost is taken for granted. How many amp stands, Rhljazz, did you actually compare to come up with your "favorite"?
Tarsando
I currently have two purpose built amp stands, a Polycrystal, and a Mapleshade. The Polycrystal pretty much sucks the life out of anything placed upon it without resorting to some type of interface like cones or flexible type mounts. The Mapleshade stand provides more of a vibrant sound and detail without limiting the power and definition in the bass. It does not force the mids/treble regions at the expense of the bottom end.
I have performed most of my materials experiments and evaluations with platforms for the power supplies of either my VAC amp or preamp. The materials I have used are MDF, solid oak, solid cherry, granite, John Boos butcher block, and the fore mentioned stands. I used a variety of spikes and flexible couplers in different combinations with all of the materials to determine the best they could give. The Mapleshade is the best followed by a toss up between the John Boos block and the MDF block. The granite and Polycrystal are just too dead. I have not experimented with any metal framed and wood stands so I cannot say how they would compare.
Years ago I bought some speaker stands that were height adjustable which I thought was a cool feature at the time. They were made of plastic and hollow tubing. When I placed my speakers on them the sound was just terrible. I then adjusted them to the same height as the old stands and they still sounded terrible, placing the speakers back on the old stands restored balance of sound. This was my introduction to "things that stuff sits on makes a difference."