We have 2 vanguards. One is a standard in 270, the other is the Accuguard that I bought when it was a Cabelas exclusive, it is now a regular item, but I think with some changes.
The 270 is my son's, with the standard stock. It shoots consistent sub MOA groups, but as it heats up, it starts to string. The barrel is the sporter weight and it is designed with some upward pressure on the front. Works great as it is, as long as you keep your strings short, my son easily made 1st round hits out to 700 two weeks ago, it was 100 degrees outside and no shade. We just had to keep it to 4 or 5 shots and then let the rifle cool
The accuguard is mine, it has the B&C stock, but I believe it is some version of the ultralight stock. At least on mine it is pretty light, I weighed it off the rifle and IIRC, it was 1.8-1.9 lbs or so. In fact, my particular rifle weighs almost same as my son's rifle, though balances differently, because the stock is so light, making up for the thicker barrel. The newer ones on Weatherby's site list a higher weight, so maybe they have changed something, but I actually took a digital scale to Cabelas and weighed it before I bought it because I did not want a 9lb rifle.
I have taken it apart and they did bed the lug into the aluminum block, and it fits tightly. The rest is not bedded. The barrel is heavier but fluted, and it is fully free floated. It too shoots sub MOA and does not appear to be as heat affected.
I almost bought a backcountry...I really like that rifle. But doing some research online, and talking to folks, it seemed that they have a hard time shooting even 3 shot sub MOA groups. My guess is that light barrel just heats up too fast? Not sure. Having just had a bad shooting rifle, I decided to go a little safer route and went with the accuguard, as I did want something that at least hit MOA, and I figured my odds were better with the Accuguard, especially after talking to Weatherby's custom shop.