Second, new is new and used is used. To me, it's just worth a few extra bucks to buy new but that's just me.
That's especially important when it comes to 1911's, even more so with the cheaper ones.
The 1911 has a huge aftermarkert, as most people know. People like to tinker with their guns, and they seem to tinker with 1911's more than any other gun out there, especially if they didn't sink a lot of money into it. Sometimes it can be very hard to tell if Bubba, the kitchen table gunsmith, decided to go to work on a particular gun and mess it up trying to do his own trigger work or throat and polish a barrel or feed ramp.
I would never buy a 1911 that has been modified from stock unless the seller could prove that the work was done by a reputable gunsmith. You could be buying a nice weapon, or you could be buying someones headache.
Since the prices are so very close together, it's preferable to buy a brand new RIA, have a warranty, and have the piece of mind that no one else has touched it.