I'm running whatever is the latest version, and oh boy is it slow. It frequently crashes, relaunches, shows me the "connections during login," crashes again, relaunches, rinse and repeat.
Every time I update it when prompted to, it sits at the "updating boot caches" screen for hours. 8, 10, 12 hours overnight, and still there in the morning. The only way to then get the Mac to reboot to continue the installation is to manually power it off. Of course, OS X doesn't like this, but other than ditching Little Snitch, I have no other choice.
For example, LS has now frozen on me for the past half hour, and that's from a clean boot.