You don't need an aluminum baffle to make a great line source using Neo 3s and 10s.....check this out:
http://www.audiocircle.com/index.php?PHPSESSID=icm8ojuu9fpe4n6k814jpbektdcpnkv5&topic=142235.0
This is a four neo 10 line source but you just build it taller and add more drivers. Three 3/4 inch pieces of highly refined particle board and 16 ply plywood green glued together.....cheap and rigid.
Thanks - that is closer to what I can see as a possibly realistic goal for the ideas rolling around in the back of my little brain.
That's what I was trying to figure out - if you made it out of MDF, how much performance do you lose as opposed to an Aluminum (or similar) frame. I think that someday I might try to tackle a project similar to the one in your link if it's out of MDF and heavy Ply. I can probably acquire the tools needed for such a project and after a bit of practice, turn out something that looks "OK" (I am no woodworker by any stretch).
I know that, as an example, Magico builds their big speaker frames out of metal to get very high rigidity, and other companies use multiple layers of stacked, CNC cut MDF or Baltic Birch to do the same thing.
Extremely high rigidity is a goal, but how big of a difference is there going to be with MDF?
The good news though is that the Drivers are now going to be available again, and those interested can start dreaming of these big (or smaller) projects again.

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PS: Did you ever take any measurements of the speakers in your link?
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