Some of the T.s. concinnus that I've had have been a bit jumpy, and some have even been a bit aggressive. Others have been just great. The T. ordinoides that I've recently acquired are extremely personable. I've only owned four of them, but they've all been GREAT little snakes. They are inquisitive, friendly, and love to be held. It'll be great once a reliable source has been established. I've had T.s. sirtalis that were also very friendly, but these ordinoides are really special. Anybody want to comment about the T.s. infernalis or T. cyrtopsis ocellatus?