Not to make you crazy, but it's so hard to tell, just by a few minutes with them. I mean, yeah, some things should leap out at you but if they all seem friendly, energetic, and they look healthy, the choice is hard.
When we (me and my fiance, newcorgiowner) went to pick out our puppy, we originally picked Matti, because she seemed the most energetic. It was between her and her sister, and we thought the sister was a little overweight and either a tad unsteady on her feet or had a slight limp. We later decided to get both. Our adventures with a weekend of two puppies are in other threads, but due to many reasons, we ended up deciding to only keep one. The one we decided to take back was our original first pick, Matti. We look at Gizmo now, tearing around and not letting us take our eyes off her for a second, and we wonder how we ever thought she was lame or had less energy. Maybe she's gotten steadier; maybe her assertiveness blossomed without her more dominant sister overshadowing her. In any case, we can't believe we almost didn't pick her.
So, whichever puppy you pick, you will love him or her though, and probably never regret your choice. Barring any obvious health or temperment problems, you win either way.
