How much thermal expansion/contraction is going to happen from room temp cure to whatever average temperature you hunt in?
You can worry yourself silly thinking about a .0002% shrinkage, a couple thousand lbs of tensile strength, shear strength or any other property you think may or may not matter.
The bedding material is only as good as the weakest component in the assembly.
My point is, quit worrying about the specific intricacies of the bedding material and use a quality product and quality processes and rock on.
The sheer number of products mentioned prove that with today's manufacturing that all of these exceed anything readily available a generation ago. I can remember when Acraglass WAS the standard all others were judged by, now there are a few that set the standard.
I use A4 Metalset because I work with it quite a bit. I am familiar with how it reacts, how to prep for it's use, how to apply it to avoid excess squeeze out, it's pot life and how it cures .
Most every product mentioned exceeds any demand anyone of us could subject it to and that is why they are so popular today.
I think moisture/humidity have more effect of POI changes in wood stocked rifles than temperature.