260 vs 6.5x55, 7mm-08 vs 7x57, 30-06 vs 308. Same arguements every time. Same classs of cartridge capability with the longer cases being able to handle longer heavier slugs a bit better.
Just depends on what you want to carry through the woods. If a 8 lb Mauser in either 6.5x55 or 7x57 or a long action 06 is a bit too much for you after hours of bustin' the boonies then the shorter cartridges in shorter, lighter weight actions might be more to your liking.
I have been sold on the 6.5mm bore for years. The first '260' I ever shot was actually a 6.5 Mannlichter Carcano and it worked very well on medium to mil/large game animals with complete pass throughs with the 160 gn 6.5mm slug. As I recall, the 120s and 140 gn slugs also worked very well.
I like my Swede - Husky made M38 that has been sporterized with scope and stock, and trigger - almost too purdy to go draggin' around inna woods but that's what it was made for. Even though sporterized and a bit lighter in weight than in its mil-spec form, the recoil is almost negligible. I s'pose that if I came across a nice 260 in just the right package I could not pass it up, and I know that, but so far it hasn't happened. Now, I'm not askin' fer die-rec-shuns to the nearest 260 store, but it could happen....I think..