[Jeph]

tqtran,
Speed limit postings in Dallas/Ft. Worth (or DFW to those in the "metroplex") and surrounding areas are usually marked when the speed limit changes at night. And it's typically where the speed limit is 70mph (65mph/night), which is outside the city.

olly986,
I don't have a plate on the front because it looks relatively uncool. It is required by law, but generally police don't hassle you for it unless they're looking for a reason to pull you over. I have been pulled over by a State Trooper for not having a plate, but he just told me to fix it.