Hi all i am getting a PJ400 from viewsonic (£450 from new) and i see the bulbs are about £300 now i know everyone must have tried a variation on this so i am asking. Specifically to viewsonic products, does any one know if bulbs of there other units fit this unit, i see the pj510 is 1200 lumins (opposed to 1600 of the pj400) would the bulb fit? i assume that going from 1600 to 1200 would make a little difference but how much? Or is there some kind of cheap generic alternative bulb? Totally new to projectors really and apart from the bulb cost / lifespan they seem like a very good toy my 32" tele just gave up on me and i live on a top floor flat and i couldnt take lugging another one up there lol. PS if there are any major issues with this manufacturer or model pls let me know. also the pj400 has a "whisper mode" supposed to stretch life span to 4k hours, which i work out for me is about a years worth of life ( or is that half life?) thanks for any info Mat.