Personally If you get the UCDP II I would get it in the .40 S&W. the .40's have the internal extractor. All the features are the same, the price difference is due to dealer profit and what they are trying to make on them hoping the consumer will not do his home work.
I would look for a good used UCDP pre series II or a used series II in the .40, or if you have to have new (and that is fine) it is my opinion that the .40 S&W with in-ex is the better choice. For your reference I bought a used UCDP II w/in-ex, Wilson mag well, 3 Wilson mags, box and all the paper work for $775.00 with maybe 200 rds through the gun.
The gun is flawless with the Wilson and Now the Cobra mags I just got, but I have had 4-5 FTF with the stock Kimber mags over 500 rounds. That's not bad I guess but that's 4-5 to many for me so the Wilson and now the better IMO Cobra mags are all I will use.
To confuse you a little, if I was buying a new Ultra today I would buy the Ultra Carry II in the .40 S&W with the in-ex and night sites.
You more than likely will have to change the mags, heck even Kimber suggests this if you are having problems with a gun feeding ammo properly. One of my friends bought a Pro Carry II with the ex-ex had problems during the first 200 rounds with FTF and FTE, called Kimber and they said to change the mag to a different kind, put another 300 rounds through the gun and if he was still having problems with it to send it in and they will fix whatever the problem is. I just bought 5 Cobra B9-MO mags for $145.75 shipped. I guess I am just warning you that however shi**y it is the Kimber mag will more than likely have to go and be replaced with a better one.
Hope this helps.
