True with projectors >6 years ago but these days very little bulb maintenance - most modern projectors have some type of "turbo" cooling system that lets you power them down in seconds rather than having to let the projector cooldown itself before turning it off, they handle motion a lot better/fine and some do really well even in fairly bright daylit rooms.
Bulbs can be a bit of hassle/cost in the long run and/or if you get unfortunate and one dies prematurely - I've been using mine fairly regularly since 2007 and only just starting to see signs the bulb might be coming towards the end of its life (takes a little longer to hit full brightness, not quite as bright as it used to be).
Exactly I'm on 2700 hours on my HD80, it's lasted me for the last 4 years, always run on eco.