The Vengeance K70 is a great-looking peripheral, with a "nice, aggressive gaming appearance" and a build that AnandTech calls "robust and consistent," due to its "excellent mechanical strength" and high-quality plastics. Both Pocket-Lint and PC Gamer called it "beautiful," with the latter saying it's "the best-looking keyboard you can pick up."
Even with its stellar design, the real standout feature is the inclusion of Cherry MX Red switches, which provide "a smoother and quieter typing experience compared to their clunkier Blue or Brown switch counterparts" according to TechRadar, with PC Mag also praising their "smooth motion and excellent typing feel" and TrustedReviews finding them "incredibly responsive" to the touch.
The other key aspect of any good gaming keyboard is its configurability, and that's where the K70 falters -- there are no macro keys, nor any macro settings. While AnandTech says this makes it feel like an "overly glorified simple keyboard," PC Gamer feels that this customization is "not going to be terribly vital, or even missed in the slightest." However, the K70 does you do plenty with its lighting, with Tom's Guide saying the "sheer variety of illumination options is staggering," with "some truly gorgeous" selections available. Unfortunately, they also report that the lighting is "much harder to control than it really should be" thanks to impenetrable software." TechRadar agrees, calling it "frustratingly difficult to use" with an "overwhelming" amount of control.
However, you don't need to customize the lighting on the Vengeance K70; you can ignore the software and just use the keyboard as-is, enjoying the smooth, quick typing experience that Cherry MX Red switches can provide. You're just going to pay a bit of premium for it.