I've owned a 4th-gen Camaro Z28, an '06 Mustang GT, and currently a '11 Mustang GT with the Brembo brake package.
When I saw the '15 Mustang for the first time on the web back in late '13, I wasn't crazy about it at all. However, over time, as better images and more information became available over time, I was dead set on getting a '15 GT Premium coupe with the Performance package.
Then, last Fall, I had an issue with the shocks on my current GT. To make a long story short, the local dealers in my area and Ford Customer Service failed miserably over such a simple problem (Sales department twisting my arm to get me a new Ford, while their service department is dragging their heels on fixing my old one), and after replacing the shocks myself, I let them know how they blew a $40k sale on a $70 pair of shocks and vowed never to buy another Ford again. I'm still getting junk mail from Ford, offering me great deals on a new F-150, Fiesta or Focus...
After scratching the '15 Mustang off my to-buy list, there were only two cars I had considered purchasing. I seriously considered a Camaro SS 1LE, but after the 2014 refresh, the styling took a turn for the worse, and I still remember the interior from when I test drove one in 2010. The interior had improved somewhat over the years, but the sightlines were just as awful now as they were then. The fact the Chevy dealers and sales reps here as just as bad as their Ford counterparts also helped scratched that car off my list.
Still wanting an RWD V8 coupe that was agreeable with my price range, I was left with the Challenger. It's not the first time I considered one before; I was thinking of a 2010 R/T, but was turned off by the size and weight (which was and is a bit bigger than I prefer) interior (which, in my opinion, wasn't much better than the Camaro, and well behind the Mustang) and what I felt was lack of performance for the money compared to the Camaro SS and '11 Mustang GT. The SRT-8 had the performance I wanted, but not for the price.
Then, last year I heard about and saw the improvements for the Challenger for 2015. I was always a fan of the car's styling, but the '71-inspired exterior tweaks really struck a chord with me (especially considering I'm not really a fan of the '71 Challenger's styling. Go figure!). The redesigned interior was also a huge improvement. But of course, the biggest improvement to me was the introduction of the Scat Pack model.
I've known about the previous SRT Core model, but it just didn't really grab me. It was still a bit too much for me price-wise, nor was I crazy about the features and options it had (or didn't have).
With the Scat Pack, all three issues I had with the Core were addressed. I still considered it too big and heavy though, and was still planning on getting a '15 Mustang, especially after finding out the GG tax would still be applied to 6-speed cars, and I had no interest in an automatic (despite all the good things I heard about the Torqueflite/8HP70).
Then, as I stated above, Ford decided to screw me over, and with the Camaro also firmly off the list, I gave the Challenger a second, much harder and longer took this time around, to the point where I actually test drove one - a TorRed Scat Pack...with an automatic. Honestly, I set my expectations pretty low.
After driving it, compared it to my Mustang, it was a very different, but surprisingly positive experience. Without a doubt in my mind, my GT is the better handling car. It's smaller, 600 pounds lighter, with wider, stickier rubber. It simply feels and is more nimble. Despite that, I still found the Scat Pack to be no slouch in the handling department. Indeed, I was actually surprised that such a large car with comparatively skinny tires could handle that well.
I also felt the Scat Pack had a better ride, and handled rough pavement much better than my Mustang (in the forever ongoing live axle vs. IRS debate amongst Mustang owners, I'm firmly in the latter camp). The slotted, 4-piston Brembos (on all four corners, no cheaping out like Ford) did a great job stopping 4200+ pounds of Challenger and look great, too (the rear single-piston calipers and 11.8" rotors look ridiculous on my GT compared to the 14" 4-pot Brembos up front, and the rear pads are a PITA to change out compared to the Brembos).
The Scat Pack I drove had the 8-speed Torqueflite. All of my previous cars have had manuals, but I was utterly blown away by this automatic. I've experienced some decent and some REALLY bad automatics (the crap dual-clutch trans in the Focus is up there), but nothing that I really considered 'good' up to now. The 8-speed just seemed to shift at the right time, every time. The shifts themselves were very quick yet smooth. At the end of the test drive I realized I didn't even put the transmission in Sport or shifted with the paddles, and I still came away extremely impressed.
The fact that the Torqueflite is only $246 more (invoice) than the manual, and is made in the U.S., unlike the 6-speed commie time bomb from China bolted to my 5.0 pretty much sealed the deal for me to go with the auto. In terms of straight line speed, I felt that the Scat Pack would get a good run from my 5.0, but would pull away without too much trouble in the end. As far as exhaust sound goes, I heard several reviewers and a couple owners state that the exhaust sounded so good, that they wouldn't bother with an aftermarket system. After 20-25 minutes to listening to that sweet 392 music from the active exhaust, I heartily agree.
As far as interiors go, I feel the Challenger is now at least on par with the Mustang in terms of interior materials and quality, but in design and technology the Challenger has a substantial lead. I love the 7" and 8.4" LCD displays on the Challenger. My Mustang only has two simple green/blue LED displays on the instrument panel and stereo. It's like comparing an Atari 2600 to a PS4. I found the seats to be more comfortable, as well. The only things I didn't really care for in the interior were the open cupholders and no parking brake lever on the center console. Outside visibility isn't as good as my Mustang, but nowhere near as bad as a 5th-gen Camaro, in my opinion. Oh, and I really appreciate the fact it has a back seat that can actually be realistically used by adult humans.
As far as exterior styling goes, well, that's a subjective matter. I've finally seen several 2015 Mustang GTs in person in my area, and I must admit, they're sharp-looking cars. But the Challenger, to me, is simply a better-looking car. It just has a certain presence which the Mustang just doesn't have. And although I don't buy cars for exclusivity's sake, '15 Mustangs are already multiplying like rabbits on the roads around my neck of the woods over the past 5-6 months. In the same time, I've seen a 2015 SXT, an SRT 392 and possibly a Scat Pack in my area. It would be nice not to run into a few dozen copies of your car every day for a change.
In the end, I still think the Scat Pack is too big and too heavy, but I don't care. My Ivory White Scat Pack should arrive at my dealer next Wednesday...one of the first things I plan to do once I take delivery is to drive to my Ford dealer to personally return all the junk mail I've gotten from them over the past five months...>