You will gain velocity with 32" but not much for the added length weight and cost. 1000 to 1200 rounds is what most guys are running of "premium accuracy" life, they will go about double that or more and still shoot under 1 moa.
The two Edges I built for my brother and I both have 32" broughtons. It looks like we get about 50-70fps over what Shawn gets with the same load in the 30" barrels. I will say that we have hit close to 3000fps with the 300gr bullet and still have no pressure and accuracy is awesome. We have backed them down to using the standard edge load to right at 2920fps. No sense in stressing things.
We are also waiting on the arrival of the new bergers. I did try some 265 aluminum tipped bullets in my rifle last weekend. Accuracy and velocity were quite impressive. I was pushing them at 3100fps with a few more grains of H1000 than we are now. I only had 10 bullets, so I didn't do alot of load work. Pretty sure I could push them a little faster, but not sure.
Our rifles balance out ok, but they are long. We used the Manners carbon fiber T-2 stocks, so most of the weight is in the butt. Recoil is probably comparable to a 270 sporter rifle, maybe a little less. Not bad at all. Our rifles weight 13.5lbs ready to rock.
I don't think you will be disappointed with a 30" vs a 32" barrel. Gamedog has pretty good luck with his 28" barrel.
Tyler the ABS barrel on my rifle is a Rock Creek barrel with the 5R rifling carbgon wraped by ABS and the Broughton barrel has the 5C Rifling. The 5R and 5C are bassicaly the same with with the Rock Creek barrel being a cut rifled barrel and the Broughton a bottoned rifled barrel
range it,check the wind, dial in correction, aim and only one shot