Nate,
Spray paint will work fine. I have done it several times. That said, I had my car sandblasted and powder coated last winter for $450. When I took the car apart last month, All I had to do was wipe it down with purple power and it looks just as good as when I picked it up from the powder coater.
The probelm with spray paint is that over the years, you will add POUNDS of paint to the car. If you get it sandblasted first, then that helps, but at that point, you might as well get it powdercoated.
If you are going to go with spray paint, the best option is to go to NAPA and get a single stage automotive paint, and spray it with a automotive sprayer. I did this with my backup car, and it worked very well. Much more durable than rattle can...