Strange X axis design

[Zeroaxe]

Hi There,

I am mainly a lurker here. I want to attempt my build sometime this year, but I have to focus on my business first! Anyway, if this is the wrong sub-forum, can an admin please move it to the right spot? Thanks.

With that said, I want to ask some opinions from here. I saw this X axis design today on Instructables, and found it interesting. For a large bed CNC machine, I can foresee a big cost in the sides. But other that that..., what am I missing? Thanks