Should I trade up? Help!

My suggestion, if you can afford it, is to throw all the $$$$ signs out the window and do what you would do if money were no option. Pay no attention to the blue book on your car or the '03, how much you owe on your car, or whatever other money generated hesitations you might have. These #'s never add up to your benefit. Welcome to the modern muscle car era.
Your GT's value depreciates just as fast as your equity goes up, so it is all relative. Besides, in 6 months or so you will be adjusted to your new/higher payments (& insurance).
Example. I have a friend who owns an '02 GT. He bought it new, did the basic bolt on's, and ran 13.70's. Fast, but not fast enough. Bought a blower and all the fixin's, and is going 12.50's now. Very fast car now and should be happy as a clam, right?
Bottom line. Has a $22,000 GT with $7,000 (conservative) worth of mods, regrets everyday that he didn't just get an '03 Cobra, at least before he did the major mod's (blower) and spent all of that money.
Now he is trying to sell his GT and discovers that he can only get $1,500 to $2,000 (or so) more than a stock GT.
Well, he's selling the car, taking the hit/loss, and getting the Cobra he "rationalized" not to get a year ago.
This is not to say that you would not be happy with your blown GT. This is just an example.

In closing, I own a Charcoal Grey '03 Cobra Vert. Fantastic car, but I understand that I just might like the 05 better when it appears, and if I do I will not hesitate to trade up if necessary. It's my only vice, but I refuse not to smile every time I start my car, and if you can afford it, neither should you.

Good luck.

Understand, that both cars started from the same place. But, never in the history of the cars has there been more differences. Even comparing '03's to '02's and earlier DOHC motors. The internals are so much better, there's no comparison. Many reports say that the internals of the 03 could handle up to 700+ horsepower.
The IRS, the tranny, the 3.55's from the factory, even the seats now are completely different.

You can wait for the 05, but already they are saying that the Cobra, in the coupe version, will be at or just North of $40,000. God only knows what a vert will go for. As you have discovered you can find nice examples of 03 verts for under $30,000, and even still find new ones for $35,000 or so.
The 35000 miles on the one your looking at is a little to high for my liking, more importantly on a car that begs to go fast. That's a lot of miles not knowing for sure how it was treated or driven everyday. That car was obviously a daily driver.

Use your heart and Ur head for this one

I went through a similar decision since I sold my 2000 Black on Blue Convertible GT a year and half ago. It sounded sensible at the time. I got an opportunity to jump up to a Cobra and I took it.

As far as thinking gas mileage is a mitigating factor my guess is that amost breathed on Mustang GTs don't get great gas mileage either. Cobras can get fairly good MPG, the '03 and '04 supercharged models are capable of getting decent daily driver mileage but you must stay out of the BOOST.

Passion is a word lots of car guy's and gal's use. When it comes to the passion most of us have for cars it usually sounds about as "Logical" as walking down the middle of the road looking for trouble in an old western movie. There is trouble out there and you can face it with a little pistol, or you can face it with a Colt 45. We are writing/talking about a Cobra Convertible versus a rather nice daily driver Mustang GT with a blower on it costing more than the Cobra without the whole package.

As for being a daily driver, my Gray '03 Cobra Coupe is a daily driver now. I haven't had it long enough to start driving it like a lil' ol' lady yet. The autombile is way to addictive. Push downward on the pedal under your right foot just once and you feel the thrust of the Super-*^&!@#-Charger slamming you into the seat the thought of what you had will quickly fade just like the view of that SS Camaro, Corvette, WRX, 350Z, (most anything short of a Viper) fading in the rear view mirror.

My advice is to think with both your head and your heart. The bank will love you for spending more $$ and your friends/competitors will say your the guy with the Cobra (read stay out of his way). You just gotta love it!

Hello I am a car addict as well. I have been battling on and off with trading in the mystic. Strictly from a financial point of view it makes NO SENSE!!!! There is just something about the new cobra that drives me insane. However I remind myself that it is an endless cycle.......when I brought the WS6 I said this was all I needed....I said that after the exhaust, I said it after the head and cam, and I'll probably say it after the blown 383. It has worked so far to bring me back to my senses, but good luck with your decision!!!!

There will always be something better on the horizon. Seriously though, wait for the 05 or greater -its that much better.