Car safety

I would not want a "t-top" if I was transporting an infant.  That type of car is more of "sports vehicle," and not a "family car" in my opinion.

I recommend a 4-door sedan or larger family vehicle, depending on the size of your family.  Also, check all the safety features (locks, windows, air bags, seat belts, crash test results, etc.) before making a purchase.  You should utilize the Consumer's Report magazine or another reliable reference source to compare the safety ratings and reliability.   

I definitely agree with the commenter above which states that this type of vehicle is not best suited towards family life. But then I don't know your circumstances, and it's not helpful to suggest this critisism since I'm sure you're more than aware of it already!

More helpful is the suggestion that you read the documentation on your car seat, and look at your state's laws regarding its use e.g. some places specifiy a child's age, weight, height, etc to be a certain level before they can do XYZ.  You should look into this in more detail.  Secondly is the suggestion to read some general advice articles (such as Finding The Best Infant Car Seat : 3 Practical Tips For All Parents) and bear their practical safety tips in mind when choosing WHICH seat to go with to protect your child.  All of that is much more relevant to your child's safety than the fact that it's a slightly inappropriate family car in which they are being transported. I hope that clarifies things for you!