I think it would be an excellent choice. The ballistics are really good and can be better with handloads. The 6.5mm bullet has a very high ballistic coefficient so it carries energy downrange very well. I have a .260 in a Rem mountain rifle and I just ordered a TC Custom Shop 15" heavy barrel with a muzzle tamer for my Encore pistol. I have shot whitetails out to 200+ yards and have been very impressed with it's performance so the .264 Win mag should be even that much better. I'm considering getting a .264 WM or a 6.5-284 as my next barrell.

Only downside I could see is that to get premuim ammo, you'll have to handload.