Wood racks and humidity


I'm thinking about upgrading my rack and like the appearance of the Butcher Block Acoustics and some of the Timbernation products. My system resides in a basement, where humidity in summer sometimes reaches 60 percent. I have a dehumidifier, which I run as needed. The previous owner of my house was a musician in a symphony, and he successfully stored sheet music in the basement here, with the aid of dehumidifiers.
The Butcher Block Acoustics website cautions that their racks should be in environments where humidity remains in the 35 to 45 percent range.
Does anyone here have experience with wood racks and higher than recommended humidities? Am I asking for trouble by buying a wood rack rather than something with metal posts and MDF shelves? I expect to move in the future, and a wood rack would look better with other furniture as part of a setup in a room of the house rather than in a basement. For the foreseeable future, the stereo will remain in the basement. 
conlad
If you want the best sounding rack that will not warp look at the Symposium Foundation.It is the best sounding rack at any were near the price.
Thanks for early responses...confirming my suspicions. To clarify about MDF, I was looking at Solidsteel series 3, which has MDF shelves that are painted. Symposium Foundation does appear to be a much better made rack that Solidsteel 3 and is priced more like the Solidsteel lower-end Hyperspike series (which has MDF shelves that are painted or coated). I'm happy to have more responses and am open to hearing about any rack brands that don't cost a fortune.
Look at Adona. They bond MDF to granite with a layer of polymer between. Works very well, but I don't worry about excessive humidity here in Arizona.
I live in the Pacific Northwest and our humidity runs from 60 to 80% outside.  I have a timbernation rack where the wood legs are screwed to the shelves.  No problems whatsoever.