I participated in the beta and was extremely impressed with my experience. It didn't "feel like blockchain", it just felt like using a regular app tbh.
The interface is smooth and intuitive and it was super easy to deposit ETH. I withdrew a part of my stake before the staking period ended and was awarded with test RPD which I immediately converted to test ETH at a 5% penalty as described. After ended staking period I withdrew my remaining test ETH + the staking reward with the click of a button. Everything is made super obvious.
Also it was very nice that there are info messages appearing after every interaction, so you know exactly where you are in the process.
I've been testing a fair few dapps in alpha and beta for the past years and this is by far the best beta I've participated in.
Full disclosure: I participated in the ICO.