Totally do it? Funny but this was a question I raised to Dogtown perhaps six months ago. I decided to make the move to 260 on his and another friends advice. I still shoot 308 amongst other things but once shooting over 600 yards with 260 you will immediately see a nice performance difference. 260 is awesome and you wont look back. It's not bad on barrels and a very very accurate caliber. Best thing is if you have a 308 all you have to do is switch out the barrel.
To answer the OP, I have shot out to 1300+ with it and it hits with authority and remains very accurate at that distance.
A must read for anyone thinking of going from 308 to 260.
The Case for .260 Remington: A Better Cartridge For Practical Long-Range Shooting