The Sony 4K projectors have a long lag time when being fed 1080p which makes then unsuitable for gaming. The lag time when fed 2160p video (i.e, 4K) should be less, but perhaps still too long for fast action games. The MSRP of Sony's least expensive projector in the USA (i.e., model VPL-VW600) is $15K and, as I understand it, authorized Sony dealers are required to not discount these projectors more than a small amount (e.g., 10%). You might find other sources selling them in the $10K range, but without a Sony USA warranty. However some authorized dealers do have 'B Stock' Sony projectors from time to time that do come the Sony USA warranty.
New projectors will be announced at the CEDIA Expo show in September, where we may hear news of new 4K UHD projectors coming from other manufacturers beyond Sony (and probably also new models from Sony).
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