I've never used Bancor... but just DEX's like IDEX and EtherDelta. In my opinion, they're not nearly as user friendly as centralized exchanges... but I do like the fact that I still have ownership of all my coins and I don't have to worry about an exchange getting hacked or stealing coins.
Yes the user interfaces and ease of use puts a lot of people off, Bancor is a bit different as it has a great looking user interface and is simple to use, this guy did a good video tutorial
https://www.youtube.com/watch?v=Z-bWTt0hejo&feature=youtu.be