I can understand your concern because I went through a similair situation recently. My first 1911 was a NIB Kimber Pro Crimson Carry, it runs flawlessly but for my size (5' 10" 160lbs), I think it's just a bit long for me to CC. I had a Glock 19 I was using for CC but the darn thing was sooooo ugly I had to remove it from my premises and I started looking around for a Kimber Ultra CDP. Once the word got out that I was looking around I had a few people contact me with suggestions about guns they had seen. One guy told me about a used Ultra CDP at a gun shop in Georgia, he held it and checked it out pretty closely. He asked the owner of the shop about the history of the gun and was told that the first owner was an attorney in town who never fired the gun that he knew of other than on the day he bought it, maybe 50 rounds. He wanted $900.
This was a tough decision for me, should I trust the guy that told me about it? Yes, he's a good guy and knows 1911's in & out. So I bought it and when it came in I was not disappointed at all. It looked brand new to me.
I think it comes down to a gut decision after you've digested all the info you're able to get about the gun. I trust Kimber 1911's and wouldn't hesitate to buy another, new or used.