True, it's no longer a system that you can really get excited about as cutting edge, and the static feature set isn't as comparatively impressive as it was when it first shipped. The iMac has stood up pretty well over the years and continues that trend. Or, if you need something with more power but that's still an all-in-one, you could wait until the end of the year and try the upcoming iMac Pro, which packs considerably more powerful Intel Xeon processors and AMD Vega graphics into a largely identical (but space gray) body. And if you've waited this long you might also want to think about waiting a little longer until MacOS 10.13 (High Sierra) ships in the fall to save yourself a time-consuming upgrade. However, if you have the 2014 or especially the 2015 5K iMac, none of those changes offer a compelling reason to ditch your current system right this minute unless it's earned an 'I brake for Netflix' bumper sticker. There are a few fast, expensive SSD RAID configurations - the fastest I could find topped out at 22Gbps (2,800MB per second) - but most current drives are designed for USB 3.1's 10Gbps maximum. The fast data transfer rate of the Thunderbolt 3 ports helps for future-proofing, but at the moment there aren't many drives that can take advantage of the spec's 40Gbps bandwidth. The Retina 5K display also remains best-in-class, as well as easier to configure than most Windows 10 systems with their needlessly confusing integrated/discrete graphics architecture. Plus, at least for this fleeting moment, it's the only all-in-one to offer Radeon RX 580-class graphics (in the guise of Apple's custom but seemingly identical Radeon Pro 580 version). This model does deliver a significant speed boost over older models, with performance comparable to current Windows competitors.

In fact, except for the Mac Mini, nearly the entire Apple computer lineup has been refreshed for 2017. These modest updates were announced at Apple's 2017 WWDC conference, alongside similar spec bumps to the 21.5-inch iMac, the MacBook and MacBook Pro lines, and even a very small CPU bump for the MacBook Air.

Late 2017 mac pro