less than 700$ best dlp projector for a +150 inches screen ?

Hi,

i am looking for a projector for less than 700$ , i'll be using the projector for a +150" screen .

i have searched for this options and i found a 2 choices

the 1st is Optoma gt750e
it comes with 3000 lumen and 3000:1 contrast ratio and with a 1280x800 resolution

2nd choice is from BenQ the W710st
comes with 2500 lumen and 10000:1 contrast ratio and with a 1280x800 resolution
( but i heard that this projector have a white dots problem )


what do you prefer from these choices ?
what is the 3rd choice that may considered with these ?

thanks

here is a test with gt750e on (190") screen
http://www.youtube.com/watch?v=glwzgA_QeQc

and i like the quality with this screen size

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