What jcarraher said is spot on. For a $40K D Driver, I would def. go with a new or newer BMW w/ warranty.
I have owned 3 Porches in my day and even contimplated your exact thread question. After reading endless horror stories (check out rennlist.com) about IMS, RMS, slipping sleeves, porous engine block failures, I quit my search for a 996. If the 996 has no warranty, you could be looking at a $20K engine replacement if any of the above (known issues) would happen. If you are dead set on a Porche 911, get a 993. They still retain the classic roof line of earlier 911's and are sooo pretty. Already a classic too.
After test driving a 135i, I was hooked. All in all a great sports coupe!