Which Throttle Body Spacer is right?

I am in the process of buying a Cold air intake and a throttle body spacer. My question is, I have noticed that they make 3 kinds of throttle body spacer. Smooth Bore, Wide Open Spacer and Swirl Torque spacer. I would like to know which one I should get, I do a lot of driving around, no towing, but just driving, which one would be best for me?
Thanks....

i would go with the smooth bore.