Wood or metal racks-Which do you prefer and why?

Me I guess I have read much about shelving material propeties ad nauseum over the years.So I guess if Mapple is way to go it can be used no matter rack I get as long as height isn't problem.I had Salamander rack and liked adjustability but always thought it was not rigid enough and those that used metal,points and cups isolated each shelf better.But as with speaker stands,especially with wooden foors,I think if I was going to plonk down I'd go for a Sound Anchor rack even though they are non adjustable (shelf hieght wise).Still when a freind with B&W803's used heavy Sound Anchor bases it imroved thoe sounbd considerably.Think that mass of heavy iron might "outweigh" (sorry I couldn't help myself) the points one might get with Solid Steel,Lovan,etc.
My Turntable I know would best be put on wall with Gingko platform expensive as they may be.The rack itself would gop below and I'd try various inexspenive sorbothane,BDR's etc.Stillpoints might be worth it but damn expensive.Only thing I wouldn't go for (on a counterintuitive basis not experience) would be expensive roller balls.But back to rack what material and design and why?
What you use to the best advantage probably depends as much on your belief system as anything. There are theories about which might be more attractive to you which will take you in a different direction.

My personal concerns considering components is, fundamentally, to provide isolation for components most possibly affected by incoming vibrations thru the floor. Its tought to control airborne vibrations and, FWIW, I don't believe that, except in theory, cement floors transmit vibrations.

To provide such isolation I like the concept of a combination of sorbothane type products with a very low resonance point in combination with a wood product with a medium/low resonance point. I would like these products not to be suseptible to airborne vibrations as much as possible as that could exacerbate the porblems they normally contribute. If you have a wood floor I would put a very hard surface under the supports of the stands to create a surface that minimizes vibrations from the floor, much like having a concrete floor. If you do what I suggest then I don't think it makes any difference whether is the stand itself is metal or wood. The sensitive components will be fairly well isolated.

If you are impressed by the theories about 'draining' vibrations from the components when the vibrations are the result of the operation of the component, and the theories involve 'coupling', and you must make a decision about competing theories and benefits, IMHO consider that 'amplitude' of the deterious vibrations (or resonances) may not create such a conflict as to incorporate or avoid both techniques.

FWIW. Sorry, I couldn't give you a simple Metal v Wood response. Personally asthetics is far more important to me as to the 'rack' itself than anything else.
red oak works for me.
Short answer. I received my S B Designs rack about a month ago. It has a foundation made with very sturdy aluminum extrusions and the shelves are thick maple. It seems to use the best qualities of both wood and metal. They have advertisements on Audiogon and have a website at steveblinndesigns.com
Wood is more musical-warmer then metal. Maple or exotic wood.
Neither - I prefer the Grand Prix Monaco Modular racks & amp stands, which use carbon fiber and aluminum/stainless supports with either acrylic (base) or carbon fiber (upgrade) shelves. Magnifique!
If you decide to go with wood, there are two or tree sources to choose from. You can probably find them on Audiogon . Do your research. I don't want to push you in one direction or the other. Don't worry those companies make their racks very rigid. They can probably custom build it to your specifications & at less one of them make shelves adjustable. Wood has excellent acoustic & sonic properties. That is why wood is so popular as a building material for instruments. Also the best recording studios include wood in they design (floors, diffusers ,stages sometimes even walls ). Wood is also the cheapest material to work with. As far as isolation & vibration control , sky is the limit. Wood can work together with other material to provide desire results. You can also try to fine tune individual component on the rack with different vibration / isolation techniques , isoblock, cones, rolling balls , what ever works for you. With that approach you can have the best of both worlds.