I must admit I'm speaking as a guy who already had 2K Server, ADS, DHCP and DNS running the last time I wanted to remotely install a PC, so RIS was fairly easy to get going.
I hadn't considered installing off a network share, I'll have to give it a go at some point.
RIS is useful because you can make installations completely automatic, so everything from installed printers to desktop resolution can be pre-configured. Which is very useful in an enterprise environment. But as Saltin says, overkill for the home. Which has never stopped me before 🙂