You didn't really mention it was for indoor use in the original post from what I could tell, so that really does change everything.
The Viewsonic, at $500 is a heck of a deal right now and likely won't be around for long.
From 11'6" lens to screen (throw distance is measured lens to screen), you can have an image diagonal between 105" and 144" diagonal. This is nearly identical to what the popular BenQ HT2050 has delivered, and really is just their version of the same model.
Lens throw calculator is here: http://www.projectorcentral.com/View...ulator-pro.htm
With about a 12' eyes to screen distance in that room I would be looking at a 120" diagonal image.
The Viewsonic should provide similar color saturation, but will have better resolution, lower inter-pixel gap, and much better contrast. In a dark room, this jump in contrast will be a huge bonus over the Sony which is lower resolution, is not 16:9 native, and is designed for bright business use.
While you may be able to use the Sony in that room, it would be a better bet to go with the Viewsonic as the best 1080p deal on the market at this time.