The only way decide which scope to get is what you have in your budget for one. Buy once and only cry once. For around the 1000$ mark you can get some high end leupold. Above that comes the vortex scopes. For around 1900$ you can step into a nightforce NXS and for the best glass around you start playing with the Schmidt & Bender scopes in the ballpark of (3000$). Good way to start figuring what you want is check them all out. Leupold, huskemaw, vortex, US Optics, nightforce, Schmidt & bender. Every one of these companies make scopes for long range shooting.