Buying a USB Type-C cable is a lot more complicated than buying microUSB cables used to be. There are various subtle differences in the spec, and a bad cable can even damage your devices. This has led Google engineer Benson Leung to review Type-C accessories in order to draw attention to the ones you shouldn't buy. The latest cable to get Benson's thumbs up is the USB 3.1 Type-C cable from Veckle (formerly iOrange-E).
This cable really has all the things. There's support for "SuperSpeed+" with a data rate as high as 10Gbps on supported devices. It's backward compatible with 5Gbps and 480Mbps as well. It also puts out 100W of power (20V at 5A) to charge anything from your Pixel to the new MacBooks.
The Veckle cable is certified by the USB-IF, and it has a special e-marker identification chip to prove it. Benson really only has one complaint: this cable does not use the proper USB logo for the spec (a SuperSpeed 10 trident logo, apparently) to differentiate it from other cables. Still, if you need a really, really good cable, this appears to be the one. It's 3.3 feet long and clocks in at $16.99.
If you're looking for something cheaper, Benson has also given his stamp of approval to the Amazon Basics Type-C cable. It's only USB 2.0, but it nails the charging spec.