A really neat thing about the netboot setup is it takes zero time to clone the image to all the machines. As soon as I'm done installing updates on one machine, I shut down, run one command that completes instantly, and now I can boot all the machines immediately with that image.

There have been a decent number of times when I actually did this during a party to fix an issue, or between parties just to keep the machines maintained for the family to play with, etc. It'd be hard to do that if I have to spend hours transferring a large image every time.

Aside from the stability issues at boot time, there isn't really a down side. I don't have any problems with load times. So I'm pretty happy with the setup.