In 2012, I had Woodhouse Dodge install a Paxton supercharger.
The Viper now produces 622HP/559TQ at the wheels, see last photo for the dyno graph.
Woodhouse is a very reputable Dodge dealer; they have installed many Paxton superchargers and I have had zero problems since the install.
In addition to the supercharger, the car has the following upgrades:
Exhaust crossover delete. Straight side pipes generate much less heat in the cabin and around the side sills
Lighter OEM six-spoke wheels instead of the heavy 10-spokes
3.55 rear end
MGW short shift mechanism
ACR short shifter knob
All cabin and cluster lights are LEDs
Chrome hoops (original ones come with the car too)
RB1 navigation radio with iPod interface and AUX port
Bluetooth (phone & music) adapter installed in the AUX port
Michelin Pilot Super Sport tires
Airbag recall done
The car comes with a cover and built-in battery tender.
It has always been stored on a lift in my garage when not driven.
Hardly seen any rain -- windshield washer fluid is still from the factory.