It's fine. I'm not going to rail about how it's unusable, or say that it makes me want to gouge out my eyes, or whatever. But it's enough to dissuade me from ever wanting to buy another Mac, if I have the option of using a desktop Linux system.

That's a pretty big caveat. But those curved window borders and the rounded widgets in e.g. the settings menu are kind of awful. Not unusable. But every time I open a terminal and I deal with the choice of either having obscene padding around my content or seeing a few pixels of my prompt's corners shaved off, I get just a little more irritated, and a little less likely to pick up my Macbook the next time I'm deciding which device to use.