It looks cool but too bad it's so heavy.
I prefer a car that can go around corners well too.
These cars will go around corners *extremely* well, with a few mods.
You can do it on the cheap with an SRT take-off suspension. Find them on EBay with sways for about $400 + shipping. Its a direct bolt-in, and since its a passenger car suspension made for a car that is designed to be a weekend track car, you get a very nice, comfortable compromise that will give an amazing boost in cornering performance. They will lower the vehicle and its center of gravity by 0.5". Which SRT they come off of matters. Challenger SRT is the softest, then the 300, then the Magnum and stiffest is the Charger. All are different only by a teeny bit in the rear except the Challenger SRT which is softer by a bigger margin on all four corners.
Next step up is coilovers and drop the ride height - as aggressive as you want to get. 1" is safe. 2" is aggressive but most effective. Lowering springs are a terrible idea on these cars. Kills the (cheap) stock shocks. Best most survivable coilovers are KW Variant 2. Then put on Hotchkis sways. Do it all at once to save on install headache. The KW's alone are around $1600 street price though. Maybe $350 for the bars. At that point you have an extremely well-handling car whose already super-stiff chassis and independent rear suspension conspire to make that heavy car extraordinarily capable in the corners.
If you have the money and the desire, urethane bushings are awesome. Sway bar end links are a help (and stiffer ones alleviate a failure point as the stock links will bend under extreme circumstances on track). There's more but going past coilovers and sways only make sense on a tracked car.
that automatic transmission you have is the WA580 - a 5-speed Mercedes AMG transmission taken off the parts shelf back when Daimler owned Chrysler. It is *incredibly* robust. Reportedly rated for about 800 hp. With the right computer modifications you can use it as part of your braking system, which is necessary when tracking a 4400 lb behemoth. So I have dropped from 3rd into 2nd at about 90 mph down to about 35 while standing on the brakes and the tranny takes it just fine.
Thats great on track. for your wife's car it means you will never lose the tranny unless whoever had the car before you abused it.
BTW since thats an AMG transmission you can hook paddle shifters up to it. On the older LX cars that share basically everything with the Challenger, all we had to do was wire into the existing connections (even the steering wheel clockspring had the unused contacts). In a street environment this is surprisingly useful in stop/go traffic-jam traffic. Makes it super easy to putt along. Otherwise not much use for it on the street except in the mountains. the newer Challengers don't have the contacts anymore but there is a setup that uses the AMG paddles and a transmitter/receiver. Moroso makes a verson too but it is expensive, has exposed wires and looks like crap.
Wat? Is that cos they're afraid the tranny won't hold up to shift shock or something?
Is there a way to disable that?
Mercedes-Benz provided the software. Its about ride comfort. Your average driver doesn't want the tranny banging between gears and chirping tires.
It can be defeated. There is the Mopar Performance Transmission Control Module for the earlier 5.7's. Reportedly it will work for the newer vehicles as well but its not rated for them. This reduces TM a lot and more importantly keeps the tranny locked up, even in 1st gear, so you can do the engine braking I mentioned. Can't happen with a stock TCM. You can also get hold of blue-top Mercedes solenoids that will do incredible things. Too incredible if you already have the MPTCM. there is also a very nice TCM reprogrammer, but I don't think it works with the new stuff.
The older cars are fully tunable. The newer ones aren't, in part because they use a rotating encryption key. Mopar just announced they are getting into the tuning market and we'll see what it brings. My bet is on limited, canned tunes but I know that a tuning provider has been given access to the decryption protocol under NDA for a special project. We'll see if Chrysler's issues with regulation are overcome by their desire to support the aftermarket.
HOWEVER, newer cars can become tunable by swapping the PCM and TCM from an older model year. That is how Arrington is making their 'new' 392-based strokers work.
For the OP, a cheap and fun mod is to put an intake on. You will be shocked at how badass it sounds compared to stock, and the sound level will still be perfectly comfortable. I developed an easy-to-assemble intake that can be had for a fraction of a commercial product. Google 'Frankentake IV'. There are literally hundreds of them out in the wild.