I'm a member of a hackerspace in Richmond, VA -
http://hackrva.org. We are in the planning stages for building a 2.x laser cutter, with the custom parts kit already in hand. Looks like a great design, with more functionality than an old Full Spectrum Laser cutter that we've been tinkering with. Once I get a handle on sources for the full BOM we should be building this summer! One question though, is it advisable to order two laser tubes so that we've got a spare around? I've read that laser tubes may not have a long shelf-life, but I don't know if that varies by manufacturer.
Thanks,
Alan