This is a topic for me. I have both I love them both.
1. Dumerils- I have one that is a great, very tame, and wonderful snake. He is one that I will just take out and hold and look at. He is a pretty average eater and never had any issues with him. He is pretty calm inside the cage but when out he is pretty active which can be very fun. He seems to like to socialize alot more that my carpet does. So if you like the way that sounds that could be your snake.
2. Carpet- Now with my JCP. She is a snake I cannot part with. I haven't seen a personality like this in any snake yet. She lives to eat. Absolutely no problem feeding with her. She will eat when she doesn't want to eat. First 4 months of her life taking 2-3 frozen pinkies and at 7 months she would take 3 hoppers but I usually didn't give her that many. She puts on a great show and never lets me down. As for being snippy, you bet. She only had that feature for a short time like maybe 2 months.
I am peticularly found of my jcp probably because she was one of my first snakes I got so she has been with me longer but I absolutely love my dumeril. so in conclusion i would say just get one of each