I expected a jump in brightness (InFocus rated 700 lumens, Optoma rated 2500 lumens) but I was disappointed when it never materialized. The contrast/picture quality is significantly better however.
I've read that some projectors have different brightness levels depending on what "mode" the projector is set on (e.g. Cimema Mode not as bright as others). I don't know too much about PJs but it might be something as simple as changing a setting on the PJ to get the brightness you are expecting. Just a thought.