1 - I tried to install 18.04 these days, it failed to install the dual-boot, an error was saying that grub couldn't be installed in the middle of the installation.
2 - The other day I managed to install 18.04 in another computer but after installation I had to hard reset pushing the button. And the first boot was all weird, the background was black, top and bottom panels were there but I couldn't click or do anything, so I had to hard-reset again. Then it worked, strange.
I don't need help with these issues, I'm just communicating what happened, overall both experiences were bad and not what I've expected, usually Ubuntu MATE installs work fine. Also, I won't file a bug report because they require more details and technical information, I don't remember all details to explain how to reproduce these issues, I can't provide further technical info because I've erased everything and installed another distro, sorry.