The H7550ST is a contender as one of the best sub-$1000 projectors on the market when considering overall Picture Quality, though it's definitely not the very best. As a home entertainment projector costing $999, it has very good color handling. I typically like to have Brilliant Color turned on, as it gives the image extra lumens and pop. With Brilliant Color turned off, it's still decent but not at the level Brilliant Color provides.
With a little tweaking of brightness, contrast, gamma, etc., you can get a fantastic picture out of this little projector. As with all projectors, you will get better color and picture quality in a fully darkened room rather than one with ambient light, but the projector still handles that very well. The color controls however, are not as capable as some others, so trying to get that last 5% of color accuracy, probably isn't in the cards.
The Acer is more home entertainment, than say, the BenQ HT3050, which is similarly bright but has better black level performance, and calibrates better (not that most owners of projectors in this price range are going to spend hundreds for a professional calibration). Although that BenQ still doesn’t have great black levels it’s more the serious projector while the Acer is more the fun projector - including gaming, where the Acer has less input lag. Also remember that the street price on the Acer is lower, pricing it between BenQ’s HT2050 and HT3050.