How big is too big?

With little or no ambient light you will have a good picture in the best picture quality mode. As your bulb ages you will either have to use a brighter mode or replace the bulb early to maintain the same brightness and 'pop'.

I run an epson 5010 on 153 inch 1.0 gain screen in a light controlled room with midnight blue/black walls and ceiling and dark carpet. Viewing distance is 15 feet 6 inches - one row of seating.

I run it in living room mode (on eco) because I like a brighter image and I think the color accuracy doesn't suffer nearly as much as dynamic mode.

It is plenty bright enough for me. If I need to replace the bulb at 800-1000 hours to keep a bright image, so be it.

In living room mode you will be fine for longer than 1000 hours and definitely more than 2500 hours when you switch to normal mode.

Thanks. I will probably always keep it on eco because I am unreasonably bothered by fan noise. Standard is not all that objectionable, but I notice it all the time, vs almost never on eco.