Pro's for the 6.5 (or 260 rem if you decide to go that route) you have a projectile range from 85 gr Sierra HP's up to Hornady 160 gr RN, I choose the 260 over the 243 16 years ago because of the heavier weights for deer, Bear, moose, whilst I could still load light for coyotes and fox, my rifle likes the 130gr Accubonds, so I stick to that load now, and am happy with performance on deer and bear,
243 has proven itself on deer, however I myself wanted a cal. With some more energy to float my boat, and still maintain less recoil as I'm smaller, hope that sheds some light on the decision, between the two id go 6.5 cm or 260 rem, pending the deal you find in the rifle platform you prefer.