Help me pick a sports car

So for some reason, my entire family has decided to start racing again. I feel a little left out and am going to jump back into to it. They mostly do SCCA racing on weekends as a family. I have owned several sportish cars in the past such as an 06 Mustang GT, 2002 WS6 Trans Am, 2002 Camaro SS and several other F-bodies.

I have several criteria in the new car that must be met. It must have 4 seats. I have a daughter and although we have other vehicles, there may be times when I need to pick her up from daycare in a pinch when I take it. It will double as a daily driver. My daily driver right now is my 06 F-250, I paid it off a while back and will keep it, but am not wanting to drive it everyday as diesel prices are high and its gas milage is horrible. It must cost less than $40K. I need to have a reasonable payment. It must be reliable enough to race once or twice a month and still be drivable as a daily driver. Also, it must be capable of not getting completly embarassed by a 10' Porsche Cayman S (dad), 10 RX08 (brother in law), 09 370Z Nismo (brother) and a 2008 M3 (father in law). I don't have to be the fastest, but want to be competitive w/ the fam. I also really don't want the same car as the one's listed above. Its more fun to have variety.

So far I have test drove the 2011 Lancer Evolution X MR and the 2011 Mustang GT 5.0. I spent several hours with each one and was able to even keep the Mustang for a whole day.

I will admit, I liked both of them for different reasons. I like the Evo's handling. I also liked the SST automatic transmission and the fact that it has four doors. The Evo seems like it can do everything very well and that it could be fast in all types of weather conditons, road conditions and can be driven fast by anyone easily. I did not like the cheap interior materials, the smallish trunk and will admit that I don't like the image the car has as being a teenager's car.

The Mustang was great. So much faster than the evo....by a large margin. It handled great too, but did not seem as crisp as the Evo. The Mustang remined me a lot of the old F-bodies I owned, but more refined. The rearend can get away from you pretty quick especially with all that power on tap. I thought the Mustang's interior was better with the exception of the seats...they lacked side support. The six speed transmission is a piece of work and I really liked the feel of it. The Mustang's back seat is also very small.

Any other ideas of cars I should be considering? I am not in a hurry to make this decision and want to really take my time and pick the best car for my needs. Also, between the two listed above, does anyone own one and have further input?