I own an EPson Projector, it's good for personal use, I already tested it sa 100-150PAX nun nag host kami ng seminar. okey naman. but for 300-500 PAX you'll need more than 1600 lumens, siguro mga 2000-2500 lumens up.

if you're looking for the best, get the infocus brand, pero sobra mahal coz it's DLP

dont use eiki dami na me naririnig na pangit daw ito.

I would suggest you use a laptop though, kasi parang may issue pag na-play ka ng avi
file sa projector, minsan ayaw lumabas or dapat naka-divx ka.