IMO you've made a fine purchase. I think the older Sakos are very well made, and also generally quite accurate. The 375 Weatherby is a step up over the parent H&H, as are almost all the 375 Improved versions. Expect its performance to be on par with the 375 Ackley Improved. Usually you can expect 100 to 200 fps higher velocities in the improved versions, depending on the individual rifle, powder, bullets, etc. I would love to see what kind of velocity you can get using the new TSX bullet.