As far as whether to go with the 3" or 3.5", I've got an express mag and am an avid waterfowl hunter and never have had any use for the 3.5". Lefty or right? I'd go lefty. personally i'm not left handed, but i have two brothers that are and they hate shooting my right handed gun. I agree with the last person. It really depends on what you wanna use it for and how much you wanna spend to trick it out alittle.