As un-impressed as I have been with my purchases of RIA (x1), Colt (x3) and Springfield (x4), (nearly all bought used) I guess I will have to advise you to buy someting new, with a bullet proof warranty.
In my experience, only Springfield lives up to that description. And I have had to take advantage of that warrantee more than once, with guns bought used. Their warrantee dept is great.
Let me stipulate that the vast majority of my purchases have been bought used.
That said, I have no plans to own another Springfield, Colt or any Philipiine-manufactured 1911 in the future.
At the moment, if I had to make a recommendation, the S&W 1911 (either new or used) would be my pick.
Other's opinions/experience may differ.