I guess I would consider several factors first. The first would be my intended usage of the rifle. If it were to be used almost exclusively in open terrain I would consider the extra two inches. Otherwise, probably not.

The 7mm Remington Magnum, even though a magnum, is a standard length case and with some of the most appropriate powders does an extremely good job of burning powder. With those same powders it is not considered " overbore" like it was earlier in its lifetime. You will be giving up a little velocity with the shorter barrel....but it will be very little. The 7RemMag utilizes 24" of barrel efficiently.

But, once again, if you are primarily hunting open terrain...or do a majority of your hunting from a stand....or just do NOT envision using the rifle in much " cover" ....the 26" barrel will gain a little, (probably 50 to 75fps). So the decision is up to you.

If I were looking at one of the " seriously large" 7mm Mags, such as the STW or such.....then I' d opt for the 26" barrel.

Good luck with your decision!