Design
The chassis of the system is essentially unchanged from 2014. It's still ultra-slim, only 5 millimeters thin at the edge, albeit with a large bulge at the back for components like RAM, the logic board, and internal storage. The similarities extend down to the rear-mounted ports, the large black bezels, the adjustable aluminum stand, and a push-button mechanism used to access the RAM panel.
As a rule this is a good thing, since there was nothing fundamentally wrong with last year's design. In 2015 it's still stylish and practical, even if side-mounted ports would make it easier to connect peripherals, and it would be nice if Apple figured out a way of improving portability or (dare we say it) internal access for repairs and upgrades.

Performance
We tested the ,799 base configuration, equipped with a 3.2-gigahertz quad-core Core i5 processor based on Intel's Skylake platform, capable of Turbo Boosting to 3.6 gigahertz. The computer also came with 8 gigabytes of RAM, a 1-terabyte, 7,200-rpm hard drive, and an AMD Radeon R9 M380 graphics card with 2 gigabytes of VRAM.
In general the system proved more than capable at handling everyday tasks, for instance letting us run Chrome, Pages, Spotify, and Slack simultaneously, with Chrome having several browser tabs open - including one running 4K video from YouTube. It was also able to handle modest games like Limbo at full speed, without hitching or dropping frames.