I agree with Redhawk500's comments in that carry of a 44 magnum generally implies a rural or wilderness setting rather than an urban one. The power of the 44 cartridge does not lend itself to urban self-defense situations because of the difficulty of control, especially with a very short barrel, and the possibility (probability?) of over-penetration of the target. Both of these characteristics increase the likelihood of what we now call "collateral damage" and are definitely not desirable qualities in an urban self-defense round.
A longer barrel in a 44 magnum permits the shooter to use more of the power of the cartridge while simultaneously improving the sight radius, allowing targets to be engaged effectively at longer ranges. That's what you want if you're in the middle of nowhere and your target is charging you like a steam engine, or seems to think you might taste good, or both. Very commonly, carry in a rural or wilderness area will not require the ability to conceal the gun absolutely, so the longer barrel won't be a disadvantage.
In my opinion, the 44 has too much power to serve well as a concealed carry weapon in populated areas. There are many better choices for that task, among them the 40, 10mm, 45ACP, and even the 9mm with modern personal defense ammunition. For carry in the field, I would tailor the gun to get the best performance possible out of the round and the shooter while still remaining reasonably carryable. The one I carry out in the woods is a Redhawk with an 8" barrel, in a Bianchi shoulder holster on the left side; but I do favor longer barrels on revolvers.
Best regards,
Trad A. Non