in my long and struggling search for the perfect varmint barrel i constantly hear brand X (insert your favorite brand barrel) will last longer thand brand Y (insert any other barrel). Im talking about stainless steel varmint profile barrels.  For instance i never hear bad things about RRA varmint barrels...but at the same time I hear  "get a douglas or krieger,shillen,Hart,etc" i realise that these other barrels arnt mass produced such as wilson and will yeld better groups but how does that affect the barrel life? a stainless steel barrel cant be that much different can they?

just the metal used, and how hard it is

thats all.....

In match shooting, chrome moly barrels lose thier grouping slowly; whereas stainless steel will go quickly.  Both will shoot about the same number of rounds before needing to be replaced, give or take.

ive been told by several people that Wilson Stainless Steel barrels will wear out around 1500 rounds? wheres other stainless steel bigger brand name barrels will around 3000-5000?

Barrel life will depend on your loads - shoot heavy bullets with hot loads and your barrel life will be shorter.  Full-auto strings will cut heavily into lifetime as well.  The longest-lived barrels (accuracy barrels, not chrome-lined) are Kriegers because the groove depth is twice that of any other I've seen.  The accurate life of a Krieger in my hands is ~2700 rounds, after which accuracy goes from sub-MOA to 4-6 MOA.  I tried a Border and it only lasted ~1300 rounds under the same conditions.  I shoot SAAMI-maximum loads os VV N-550 with Hornady 75 gr bullets; others who shoot lighter loads get 2-3 times the life.