The Shotgun 650 has an 18" front wheel and so that rules it out for me. Current first choice is the Yamaha MT07 AMT, followed by the Ducati Monster.
Less Old Fart & more yahoo! The Yamaha MT-07 is widely considered a "hooligan" bike due to its strong, low-end torque, aggressive power delivery, and playful, wheelie-friendly nature, making it extremely fun!