What ever you do decide to get, if you have not done so already, it is usually a good idea to find out about your financing options before you go to the dealership, especially if you have good credit.
When I got my 300C, I already had to good offers in my pocket and gave the dealership the option of matching the best one; if they had been a pain to deal with, I would have asked them to beat the offer, but they were easy to work with(and I told them why they did not have to beat my offer, only match it). Basically the dealerships get some money for doing the financing.
Also, if you plan on getting an extended warranty, shop around online(I would only go with Maximum Care from Chrysler). Depending on the age of the two 05s, their may not be a penalty for getting the extended warranty. Also, the 05s have a 7/70, which I believe is cheaper to extend. And, when you extend, if you pick a lower deductible, it applies immediately.
But, it is also possible that either of the 05s may already have an extended warranty, which would be transferrable to you, for a fee. Make sure to ask.
Opinions vary on the extended warranty(whether to get one or not), but for me, I like the piece of mind. With the prices I got, I decided to go with the $50 dedcutible, which I would break even on at about 3 warranty visits. And, pick the plan that fits your driving. Me, I drive a lot, so I went with a plan with 100,000 miles, but fewer years. For some, low milage but a lot of years works for them.
In short, the better prepared you are going into the dealership, the better your chances of getting the best deal. I don't mind the dealershihp making money on me, I just don't want to be gouged. I even made sure to have my title, registration, and insurance info with me; the dealership new I was serious and not there to waste their time(and they knew I wasn't going to let them waste my time). I am firm, but also fair.
And, finally, enjoy the car...but that won't be hard to do. :biggrin: