Well as similar as the Magnum is to the Charger, obviously they are VERY different. Your maggy's going to have alot more room than the charger. I believe the 2011-13 V6 chargers have the 8-speed transmission that I hear works VERY nice. And I can tell you first hand, the interior of the 2011-up's are awesome.
Just be sure you have enough room if you downsize to the charger. But I'm sure, you'll love the new charger if you decide to go that route.
Also, if you find a Mopar 11, they're a hot ticket with 3.91 gears. Enjoy the search!
Current 2013 Dodge Charger SRT8, Corsa Extreme exhaust, 20% window tint, AEM drop in filter