Please check my design for a downfiring dayton 8"

I'd like to know what people thought of this design.

The driver is the 8" dayton quatro SVC 4 ohm.

Dimensions (without stand)

Outer Height = 21.75"
Outer Width = 9.5"
Outer Length = 9.5"

Inner Height = 20.25"
Inner Width = 8"
Inner Length = 8"

.75 ft^3 internal with 13.9" total port length and 2.5" inner diameter (exactly to dayton's spec)

The legs are each 6" (this is what I'm mostly unsure about.) I don't know whether or not they will be real wood or PVC.

There's approx 3" of space between the driver magnet and the bottom of the port. I thought this was acceptable since it was more than the inner diameter of the port.

I'd line the walls with some acoustic dampening material just like dayton suggests.

I already did the driver sag calculation for the dayton quatro 8 and it was somewhere around 2% of xmax indicating that the driver is OK for this downfiring application.

Any comments are appreciated, thanks.