I only use Dadice, it is the future of dice site, it implements social media features, we can chat in the site, besides, send or get tips in the site, which is the most awesome function. Additionally, dadice has the best faucet.
I used JD before, but there was not faucet, no fun.
The only thing that is not good in dadice is the speed of the site. most of the time the site is slow fir me even using the light version