Oh yea! 6.5" is a great length! Ported will allow you to shoot that puppy all day long! I have several ported 44's and some with the weights and some with both the weights AND ported...the porting turns the 44mag recoil into 44spl recoil....you NEED that S&W!
Most of these are 44mags, varying barrel lengths and styles. For example top left, second one down is a Lew Horton 44 with a 6" ported barrel with the weights. VERY easy to shoot any 44mag ammo! Two down from that, is a 329PD, 4"bbl, NOT fun to shoot 44mags out of, but the one below that is a 2001 Stealth Hunter "naked" with a 7.5"bbl ported, also easy to shoot(came like that from the factory). To the right and up one is a Dan Wesson 44mag, it is a 4"bbl with a 5" barrel shroud with the ports, you can shoot that all day long!
But you are on the right track! I think regardless of the Smith you buy it is a win win situation!