Cosmetics aside, if you are shooting a fairly overbore caliber you want a stainless barrel. The throat erosion appears different, through the bore scope, on stainless. It looks kinda like a mud puddle that dried up and left a pattern of flat areas with check cracks in between. A CM (blued) barrel's throatlooks like a gravel road or rough sandpaper under the scope. Both types of steel will exhibit throat erosion over a certain number of rounds, but the stainless will usually hold its accuracy a little longer - like maybe 25% or so. If the rifle in question is a standard caliber like .308 or .223, there doesn't seem to be any meaningful difference in accurate barrel life. And there is quite a bit of evidence out there to suggest that the CM barrel can hold up to poor barrel maintenance a little better than stainless.