Dust Free (?) Enclosures

The dust enclosures sold by StepCraft (and others) are quite expensive, so I am wondering why they are popular since there is danger of heat buildup at the spindle. In America, there is a company called 80/20 who manufacture an extensive line of extruded aluminum constructs. When I was a kid, I always wanted an Erector Set - this company calls their products "The Adult Erector Set". I have given them a lot of business with projects like a paint-spray booth with fan, heavy-duty roll-around dollies, and an adjustable height work table.
Following Mmorao's cautions on heat buildup, I plan to cut a 4" circle in the 1/4" acrylic back to mount a blastgate for the dust collector's hose. The front, top, and sides can be less sturdy, using 1/8" clear acrylic. The 1x1 aluminum square tubing, with flanges on 2 sides for the clear panels, is very lightweight, easy to cut, and fits together with corner connectors.
What I have yet to resolve is how to route the air tubing and power cable to the spindle as they travel along the X axis. Perhaps a narrow channel (padded with soft tape to prevent abrasion to the tubing and power cable) at the top/rear, or top/back.
If successful, I'll post photos next week.