That's a pretty broad generalization. It would all depend on the denier of the silk. What are you comparing really? Kevlar as thick as a sweater and silk as thin as stockings? Or the other way around?
If we are talking pure stopping power we don't know how thick a weave or how many layers we need to even compete with kevlar at an even pace.
The only real comparison we have is mundane silk. You have mundane silk at $21 a yard for whatever that yard happens to be. I do not see a matching yard of DS going for less than $50 A matching MS yard would probably be around $30 IMO to be competitive in the same market with the benifit of spidersilk as the premium.
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