I'm 6'5", and when I sat in one it felt a lot like my wife's 4Runner as far as headroom goes.
Can the 07 be ordered without power seats? I used to be a Firebird guy (hence my screenname), and I couldn't fit well in a Trans Am, because they all came with power seats from 1998 onward. However a Formula Firebird with manual seats worked real well for me. Since they didn't have to cram a motor underneath the seat, it sat a little lower, which made all the difference for me. If you really want an 07, see if you can get one with manual seats, and see if it makes a difference. Something to think about at least.