I’ve had an account there for 5 years now.
Two whole things posted!!! I’m just bored and replying to everything. Sorry.
Actually, if you’ve not been there for a while, Conceptart.org has at come point re-vamped their account things to make them sort of resemble deviant-art, but i do think they have some better customization stuff. I’ve not actually tried it or explored at all, but maybe worth a look?
EDIT - They reserve the right, i believe, to use your subbmitted artwork in advertisements and stuff for their site. You do retain all the copyrights and everything to the art. If you choose to use their print service they take a chunk of the profits, but then that’s obvious. But yes the stuff you post there is legally yours, they can’t sell your work to anyone without your permission. They just put that there so they they have the right to display your work publicly. Which is what they do, basically.