Are you using v-flats? what material? where to buy?

I'm looking to get V-flats for my studio, but have a feeling a foamcore would be too flimsy and unstable... also might wear out too quickly. Any recommendations on materials you make your v-flats from, and where to get them?

Thanks much!

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Shaq
http://www.shaqphotography.com - Commercial Photography
http://www.GoSeePhotography.com - Lifestyle Photography