I kept going back and forth between these two snakes for several months last year and early this year before I decided on a corn. I'll tell you why I chose what I did. I won't bother going over why corns are good (this is a corn snake forum, just look around and you'll find thousands of examples why). Milks are good too, but when I sat right down and made a list of good/bad things of each species, the milks had more negatives than the corns.
Do you want this snake to show other people or just to say that you have it? From what everyone on the milksnake forum told me (keep in mind these are the people who should be pushing for getting one), they like to hide a LOT. I want to be able to use my snake in an educational setting, so that was a negative point on my list.
You want to handle it at least once a day? The same people that told me they hide a lot also told me that the Mexican & Pueblan milks are very flighty when you pick them up, and sometimes even musk or bite. I was told that if you got one and it ended up being like this, it was likely never going to grow out of it.
I'm not saying "don't get milksnakes." I'm actually thinking of getting one this summer...but it sounds like this is your first snake, right? You'll want one that is going to put a positive spin on the situation. And by the way, on my list, the only negative "point" I had on the corns side was that they don't look as nice as milks in my opinion...but I can live with that.