it's your first cc, so you're probably going to be paranoid about printing no matter what. You'll want the shield. I did the same thing a year or so ago, certain a single stack was for me.
Once you get comfortable though, find the right position on your waist, the right holster and belt (this means ALOT, seriously) you'll start to notice you can carry much larger pistols comfortably and concealed. I'm in the process of searching for a compact double stack to replace my kahr right now.
I'd say go with the M&Pc