Mike50, there's light, as in Winchester, and then there's Weatherby. Even their standard barrels are as thin-walled as a Win Featherweight.
Now, I fully agree that if one is a handloader, and tweaks and tunes his loads, Good Things can happen. My reply was based on the average fella who buys the rifle, buys a box of ammo as suggested by the salesman and goes out and "has at it". If it will shoot a good five-shot group, great! Howsomever, I have seen too many guys go to the range with their new pet and be sorely disappointed.
I think the Wby UltraLight would be a great walking-hunting and high-country rifle. I just wouldn't be surprised if it took some effort to get it to shoot tight groups of five or more, is all...
Regards, Art