5. Its seems like there is no user-specific secret in addition to the master password. If two users happen to use the same master password (which is definitely a possibility, especially with weak or easily memorizable passwords) they will basically have all the same passwords for every site!
6. Rotating your passwords regularly, at least for your highly sensitive accounts, is very important. With this approach, you can't change any one of your passwords without changing the whole lot (i.e. changing your master password) which simply isn't practical.
7. They serve the whole thing over the web, which, as has been pointed out many times over the web[1], is a bad idea.
Overall, its seems like they are looking for a overly simplistic solution for a complicated problem.
<shameless plug>Padlock[2] is a penetration-tested, open source password manager that, while using a battle-tested, 'conventional' encryption scheme for securing data, still tries to be forward thinking and to improve on the overall user experience of other password managers.</shameless plug>
[1]https://www.nccgroup.trust/us/about-us/newsroom-and-events/b...
[2]: https://padlock.io