It's not here because it is developed by Xiaomi EU guys and their forum, so remains there. It is based on the most recent branch of the Chinese stable or beta release.
As it is based on the Chinese versions, it does have some translated Chinese apps like the theme app but has lots of pluses too as well as getting updates earlier normally. As for performance, well it is not the fastest ROM if you're a gamer or constantly looking at performance scores but as a good all round ROM, it's the best I've tried. But as I don't like Google dialler, contacts and text apps, the Xiaomi versions are great for me.
I don't like it when I hear people slag it off as terrible when most have never tried it and just listen to others giving it a slagging who also never tried it also.
There must be some good in it as the very few custom ROMs being tested for the 11Ultra are all based on it!
To install, unlock your bootloader, boot twrp, flash the ROM, format data and away you go. Updates are by ota still. Now that's not a mess or difficult. And you don't even need to join Xiaomi EU forum to get it, just head over to mifirm.net .