Hey Blue Man,
I just talked to Ayce on the phone today.
Fresh off the oven, (I have 5 yards of it), is a better quality Climashield.
The scoop is the Clo should be right at 2.0 and the material will not clomp in spots when unrolled. He is also looking at getting some specially made 5 ounce Climashield.
Ayce says that the material is spun a little different which gives a better lay and higher Clo.
I'm sure there's a lot more technical jargon to it than that but as long as the out come is good, the rest is just something Richard N. will have to update us on.
Any way, I wouldn't worry about the 3 layers being too much at all.
I would use about a 3-4" strip of Momentum to sew the edge of the entire circumference of the Climashield layers together with the thread going through both the top and bottom of the strip, (clamping it).
This will give you a lot more support and it will be much easier to attach it to the Momentum shell.
You are going to have one warm quilt. What temperature do you expect it to get you down to?
The 3 layers may be a little over-kill.