I have been using Clover for several months now and have seen it evolve significantly. In terms of EFI boot, similar to Chameleon, Clover is much better in my opinion. More things work seamlessly, especially with a properly patched DSDT.
UEFI boot has also changed a lot over the course of the last few months, but it tends to have more issues on certain configurations. Some issues have been solved, but others still remain. Issues such as sleep, restart, incorrect CPU/RAM frequency detection, among other issues, still remain for certain users and not for others. The use of certain drivers also causes issues as well. I'd recommend CloverEFI over UEFI, but for both, it's best to test using a USB before doing a full install.
Linux distributions, Windows, etc. work fine.