98Bravo or MRAD
I have put about 40-50 rounds through each and I prefer the MRAD. It just feels better to me when shooting it.
That said, you are going from shooting at 800 yards to a rifle that doesn't come into its own until 1700 yards. In my opinion, you should consider something a little less and work your way up. The .338 LM really does not cost that much less than the .50 to shoot, and you can buy a .50 caliber rifle for the same price as the MRAD. Something like a .300 Win Mag will outperform the .308 without hurting a wallet like a .50 or .338 LM.