Here is my opinion of the two:
If you're about the looks, then the best bet would be the Spec-V. Nissan makes some bad ass cars and this is no exception. That car has some balls and can hold its own against some of the other sport compact sedans. The thing about a sedan though, is that it can't haul much as far as cargo goes. Its only a sedan and is limited by what it can carry. Now a P5 is a wagon....which when you look at it is still a wagon. But... its a very sporty, sleek looking wagon. With a little bit of aftermarket help, it can look just as slick and sporty as the Spec-V. Plus with all the parts becoming available as well as turbo kits you can go just as fast as the Spec V when its stock.
I also wanted to mention that I find it a bit humorous that you come to a Mazda forum and ask us convince you to buy a Pro5. I think you already know what you wanna buy but you want us to confirm your thinking. Of course most of us are going to be biased and say buy a Protege 5. Thats why we are all here. Its not too often you see someone with a Honda, Acura or Nissan visiting regularly on a Mazda forum.
But to answer your question, I say go with the Pro5. Not only will you be getting a reliable car that handles well for a "sport wagon" and has decent HP (but numerous amounts of potential), you will also be getting a family of Mazda owners who will help you out with anything you need IF problems arise.
