I would choose the 6" barrel, but then again, I wouldn't even consider attempting to concealed carry a Model 29 since not only would the size/weight make it difficult to do so, but .44 Magnum is overpowered for the role, and I would be concerned about the possibility of overpenetration/collateral damage. (Granted you could use .44 Special, but it's still awfully big/heavy for a CCW.)

The Model 29 is more of a Wilderness Defense/Range Gun than a Concealed Carry piece.