Adorama’s official eBay Store offers the Dell 28-inch 4K LED Ultra HD Monitor (model S2817Q) for $399.99 shipped. That’s down from its original list price of $600, $46 less than Amazon’s already low price and the best available. You’ll be able to take full advantage of 4K resolution with this 28-inch display from Dell. Features include picture-in-picture support, 9W speakers, two HDMI inputs and dual USB ports. Rated 4.4/5 stars by 188 Amazon reviewers.