You probably need to determine what your primary use will be. Do you need it to be concealed? Do you need a longer sight radius for better accuracy? Will it be your only firearm and will certain compromises be made for that reason? Is the caliber a wise choice based on your experience and needs?
You'll find as many opinions of what you should buy as there are people.

The bottom line is there are trade-offs for any variations you choose.
The short barreled guns require more practice to become proficient with. They have a much louder noise report and because of their lighter weight, more perceived recoil. They shine in the conceal-ability, handiness and lighter packing weight categories.
The longer barreled guns are easier for new people to shoot accurately. They have a longer sight radius and the longer barrel length provides more weight forward, effectively reducing the perceived recoil, noise report and muzzle flip. The negatives are those things that can make the short barrels a better choice.
I have no way of knowing what your shooting experiences are. My own current favorite shooter is one of the same guns you're considering, a 629 5". They're great guns but if this revolver will be your first gun I'd suggest you may want to consider the .357, 45ACP, or the .41 Mag also. They tend to be a bit tamer as well as capable for the new shooters.
Good luck! Let us know what you choose....
