I have owned and driven my SRT-10 for one year now. I have owned and driven previous Vipers, Corvettes (Z06's included), Cobras, and supercharged F body vehicles. Without question, this vehicle wins hands down in every performance category imaginable. There is simply nothing better than feeling this car's 525 lb/ft of torque at your back. It is accentuated by the ability the vehicle has to actually grab the road. I have been more than impressed with build quality and interior design. Some of the SRT's flaws are undeniable: incredible heat flowing through the passenger cabin as well as a propensity to follow road surface flaws exactly. But I absolutely love my Viper.
Torque (boatloads of it), exterior design, exclusivity (everyone sees Corvettes; Viper spottings are special). Stereo system is good. Performance and handling is phenomenal.
Take care of the interior heat problem. Give the exhaust a non V10 sound (difficult, I know). I little more leg room would still be appreciated. Figure out a way to improve mileage without sacrificing power. I wouldn't however, accept the former at the expense of the latter!