I don't see B&C as upper tier, I'd rather have factory tupperware.
I've used McMillan, Brown Precision, and Hi Tech Specialties in the past. Those companies as well as MPI and Manners build stocks using lamnated layers of fiberglass or kevlar cloth in the action area through the pistol grip with an outer shell of cloth on the other areas filled with foam to deaden the sound. The action is milled out just like a wood stock. It makes for a very strong, lightweight stock. Especially kevlar.
HS Precision and B&C mix chopped fiberglass (think attic insulation) with molten plastic and pour it in a mold. They use an aluminum bedding block in the bedding area and grip for strength. It makes for a strong stock if it has the metal inside, but also a heavy chunky stock. OK on a heavy varmint or target rig. Not what I'd want on a hunting rifle.
