unless you plan on taking sweeping turns at really high speeds you'll be fine without a wing. The rear end may feel a bit light but you won't lose the car unless you're trying to take turns and even then you'll probably be ok, a wing would simply add downforce making the car more stable. I personally love the look of wingless carreras.

 

Get a 997 areo wing. The GT3 will not fit.

 

with the aero wing do I still have to get a GT3 fan or the stock fan would fit??

 

GT3 fan

 

The aero instability that results from having only the front bumper is a bigger issue if you plan to decelerate, after accelerating to a high speed, while turning... Since one can't guarantee that there would be no need to lift or brake while driving around a sweeper fast, having the rear wing would be help in keeping the rear end behind the front. =)

That said, the difference in steering feel between non-aero and aero, on a 4s, is definately perceptable at speeds < 100. The GT3 aero kit is even higher in downforce.