I have a Bergara HMR Wilderness. No experience with Sako. The Sako is a lot more expensive, which suggests higher build quality.
I'd suggest not messing around and just get two rifles. The same rifle for stalking and target (assuming it is prone target, for accuracy rather than fastest speed) is a compromise for both. For target, the HMR stock is good, but it is not as good as a chassis. The reason I bought the HMR was basically cost - the amount I've been spending on guns was getting excessive and I didn't feel like paying the additional £1,200 to get another chassis rifle of some kind. If cost were not a consideration, I'd get a chassis. If you get a chassis, you can also get a foldable buttstock which is a big plus.
If you do get the Bergara, then it is the HMR that you want as AFAIK that can come with the heaviest barrel, 0.85 inch diameter at the muzzle.