I did the same analysis (270win vs. 6.5cm) a couple years ago and it was an easy choice to go with the 270 for my hunting. If I was ever in need to reach out to where the 6.5 out paces the 270, I'd be shooting my 7STW, 300wby or 340wby. If I had ready access to long range shooting area (my front yard range only extends to 363), I'd consider one of the 6.5s. FWIW, my favorite cartridge these day for deer is a 270wsm shooting 140 accubonds. For my farm where shots average in the 225-360 range, I still find myself drawn to the wsm even though I've seen what 130s at 3100fps due at those modest ranges.