I was talking to the owner of ABS and he mentioned that Chrome vanadium steel barrels are more accurate than Chrome lined and Stainless, but the accurate life tapers off dramatically, and not gradually as with stainless.
The Stainless barrels while slightly on a very small scale less accurate than chome vanadium steel are likely to give you 2-4times the accurate life of chrome moly, and that gradually tapers off. From what he was saying it sounded like stainless was a far better idea than chome lined or chrome vanadium.
I do not know how that compares to chrome moly, but my point is that for what you are talking about, the accuracy isn't so much your major concern, as is accurate life, which is a cost and performance saving measure.
It's looking like one of the stainless polygonals is worth more than four chrome lined barrels as 5000 rds usually have chrome lined barrels shooting worse than 3-4MOA and in need of replacement.