It is very possible to carry a full size gun, I know of a girl who carries a full size Kimber 1911 and she is 5'5" at most and probably 115 lbs soaking wet. IMO some of the most important factors you choose your firearm whether its a sub or full-size is can you handle it safely and shoot it accurately? /Rant If you have 13+1 and two spare mags on habd but can't shoot for shit then..you have a nice paperweight or possible melee tool. /off rant IWB/OWB is preferential to your comfort and abilities to get to your firearm IMO use the one that works best for you, there is no reason to just use one style of carrying , Like Kawi kid said its easier to carry a larger gun in the winter. Personally I thought i would never carry IWb because of my skinny frame however its how I prefer to carry, but it's because my IWB holster is excellent. Mykill, Tthere are two other very important factors when you start to carry your choice of firearm on a regular basis and they are Holsters and Belts. 1. You want to make sure that you get a good quality holster that has excellent retention but still allows for a smooth draw. You also want to make sure it has two location that attach it to yur belt this way the weight f the gun is disributed evenly and the holster doesn't shift positions on you. It would suck to try to draw in a stressful situation and your firearm is not where is should be. 2. Make sure you get a good quality belt so that your firearm doesn't drag on you or flop around again making sure your firearm is where it is supposed to be. You can buy some nice thick belts (iv'e heard ) in Amish country and there are plentyof places online.