stainless vs. crome-moly (4140)
Personal experience:
With Model 70 Winchester Target Rifles (course guns), I had quite good results, and as I recall 6000 plus round life from the factory barrels. I speak of 30-06 and 308. There would be throught erosion certainly, however adjusting loads to compensate was doable, and results were quite good, I thought.
Once had a Hart Stainless tube on an 06, it was very accurate, but as I recall, did not seem to last as long as the chrome-moly barrels did.
As for replacement barrels, Douglas at Crosslanes W. VA, that's near Charleston used to do very good barrles. The last time they did anything for me was more than 10 years ago, but back then, they did a very good barrel (premium air gage), and installed them well too.
The gentleman that used to run their shop, Tim Gardiner and I got to know each other slightly, and on the subject of choosing between satainless steel and chrome moly, as I recall he once said that for the difference in price, he did not think that the stainless barrel was worth the extra charge.
Other than that, pay your money, take your choice, and hope for the best. By the bye, a Remington 40X that I had came with a stainless barrel, from the factory, which was very accurate.