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The iMac with 4K Retina display is an excellent computer that once again offers something you can't easily get from Apple's rivals. Be warned, though, as you'll want to upgrade that spinning hard drive if you don't want to be sat twiddling your thumbs waiting out slow boot and resume times.
We liked
The 4K iMac's display is nothing short of stunning. With bright and vibrant colours, support for the DCI P3 colour space and a high enough resolution to ensure that the desktop never feels cramped again, the machine is a pleasure to use. It's mostly fast enough, save for the meandering standard hard disk drive. You'll be satisfied with the 4K iMac's excellent speakers, which won't beat a dedicated pair in most instances, but are more than sufficient for listening to music, watching movies, streaming TV and light gaming. There's arguably enough ports for now, with USB-C expected to come to a future model.
We disliked
Apple so very nearly got the 4K iMac's entry-level specs perfect, but the lack of a Fusion Drive as standard is a poor show. That gorgeous display soon loses its allure when you're tapping your foot waiting for it to boot – so do yourself a favour and upgrade to the 1TB Fusion Drive - or even the 256GB SSD for best all-round performance. It's also about time Apple put a height adjustment stand on its iMac computers, so you'll have to balance them on a set of books or buy an accessory to lift it up to eye level until then.
Final verdict
There's no question that the 4K iMac is in every way an improvement from the standard 21.5-inch model. Even if you wouldn't take advantage of the extra screen real-estate offered by its 4K display, the additional clarity it provides makes the 4K iMac a much more enjoyable computer to use. There's less eye strain and OS X El Capitan takes on a new dimension, one that's enriched with colour saturation, sharpness and detail. On the other hand, if you would make good use of the extra screen size (and higher resolution) afforded by the 27-inch 5K iMac and require extra graphical grunt for playing the latest games, you should strongly consider spending the extra money on upgrading to Apple's biggest all-in-one.
