Goto remmingtons website, get caliber info on a VS. Than check the ballistic charts for those calibers and ammo available for hunting deer. Cross reference that with the 7MM Rem Mag and the bullet you use. The magic number is 1000 Foot pounds of Energy at the distance you want to shoot, to be consider reliable, ethical, lethal or whatever for hunting deer.

Example a Rem 6 MM shooting 100 Gr corelokt has about 1000 at 350, given a 7 Rem Mag with 150 Grain Corelokt it is something like 600 or 700 yards.

Another useful tool Remmington use to have is Rem. Shoot it is a free download Ballistic Program. Check it out it if available it maybe able to help answer some your questions and narrow the choices.

I personally think if you want long range you need to up the power, just as a rule of thumb use the 1000 lbs rule.