Ovny, the 300 Win Mag with a 25" barrel will give you close to maximum performance and may even be better performance than another rifle with a 26" barrel. Other things such as free bore, twist, and how smooth or polished the barrel is can make more difference than another cm or two.

A 26" barreled rifle still looks nice and in proportion and is still handy enough in bush or in vehicles, I know because I have used one for much of my hunting years. In any rifle and barrel combination, the longer the barrel the more performance you will get especially with the slower burning powders, you just have to choose what suits your hunting.