My Dum is heavy. She's about 16 and a half pounds and is a ground snake. I lift her and support her over my shoulder until I can sit down. She usually curls up around my waist and and in my lap as I watch TV. She just chills. She'll flick her tung and look around for a bit and usually rests her head on my knee or arm and watches TV with me. I think se actually does watch the changing lights on the screen. Every once in awhile she seems perky and wants to explore but she usually stay with me.
She never has an aggressive attitude even when in shed. She usually goes off food every winter for about 125 days. I know that she'll start eating soon when she sheds around that mark. As soon as she gets that last bit slid off I offer her a large rat. I always feed with tongs because they are an ambush predator. She has never missed but she hits so hard that she has occasionally left me standing there with a tail swinging from the tongs. I know they aren't as flashy as a lot of other boas but I just can't imagine life without her.
She is also the first snake I bring out for a curious person who is scared. Yes she is big and heavy bodied but she is also slow moving and doesn't mind the attention. People are always fascinated by how smooth and dry she is and almost aways feel brave enough to hold her in the end. She was a severely abused rescue that I got a couple years ago. Its amazing that she went through hell with humans and still be so mellow and comfortable with us.
I can't say all Dums are like my Leelah but she is the perfect medium snake.
Edit: I should point out that my Dum is under weight. She was 6.5 feet and 10 pounds when I got her. Its been a slow but steady job putting good weight back on her. She never loses weight during a winter fast but it slows her gain. Just be prepared for a much heavier bodied snake that a BCI.