I use it every day, but onyl for it's CMake support, syntax highlighting and 'go to definiton' etc functionality. I don't use it for building though, that's still done on the command line.

I did! Mainly on Linux because QtCreator is one of the very few Linux IDEs where the debugger worked out of the box (now I switched to VSCode too there, mainly because it allows the same development environment across Windows, Linux and Mac).

True, QtCreator performance is fine. But I found the whole toolchain integration (Kits?) and cmake integration a bit weird if I remember right.

Don't do C++ now, but when I used to QtCreator was such a joy to work with.

The fact that it played so nicely with CMake was an added bonus.