Part of the reason, if not reason people buy mechanical keyboards from the likes of Corsair and Das Keyboard is for that sweet, sweet extended key travel. The mushy membrane keyboards included with most desktops and the cursory chicklet keyboards of laptops simply don't have the depth of key travel and tactile feedback that rapid-fire typists and gamers demand. If you fall into either of those camps, I'd urge you to give a mechanical keyboard a try—it really does make a world of difference.
Weirdly, though, Corsair thinks the key actuation of a good mechanical switch is a little too high for the most l33t of gamers—they might even be losing precious e-sports dollars because of it. Enter the K70 and K65 Rapidfire keyboards, which are kitted out with the all-new mechanical Cherry MX Speed switch. The MX Speed boasts an actuation distance—that is, the point at which its switch is activated—of just 1.2mm and a light 45g actuation force. By contrast, my mechanical switch of choice, the Cherry MX Brown, has a much larger 2mm actuation distance and 55g actuation force. The idea is to give an advantage to e-sports players by shaving off precious milliseconds (microseconds?) from each keystroke.
Now, I know what you're thinking, and no, if you're not into your mechanical keyboards, it's doubtful you'll be able to tell the difference between an actuation distance of 2mm and 1.2mm. Even if you are, the difference is subtle. But, there is a difference, and I'm not so sure it's one I like. When compared side-by-side with a Cherry MX Brown keyboard, the Rapidfire's keys aren't as comfortable to type on. There's no discernible bump or click—one of the key selling points of many mechanical switches that helps identify when a key has been pressed—and the shallower travel makes it far easier to bottom out when typing.
The Rapidfire has a very similar feel to Logitech's G-series of mechanical keyboards, which boast the company's own Romer-G switches. The Romer-Gs also sport a low actuation distance and operating force—1.5mm and 45g respectively—and rather than help e-sports players hang onto their dollars, I suspect the Rapidfire is meant to help Corsair not lose any of its own to Logitech. Regardless, the shallower feel isn't one for typists, and even gamers might find that the reduced key travel negates the whole point of owning a mechanical keyboard in the first place.
That said, it is largely a matter of preference. If you're a fan of the Logitech G-series or you like the smooth clickless feel of a Cherry MX Red or Cherry MX Black switch, the Rapidfire is good choice, particularly as the rest of the keyboard is extremely well made. The chassis is made from a solid brushed aluminium and sports non-obtrusive but useful extra keys like a Windows key lock (which puts a stop to accidentally bringing up the start menu in the middle of game), as well as dedicated media keys and a lovely knurled knob for adjusting volume.
There's a comfortable detachable wrist rest included in the box too, as well as extra contorted and textured keycaps you can use on common gaming keys like WASD. Again, I don't think they make a huge difference to playing games (when was the last time you couldn't find the WASD keys without looking?), but it's nice to have the option. Round the back of the keyboard there's a USB port for hooking up a mouse or other peripheral, along with a largely pointless switch for changing the polling rate of the keys—why you'd want it at anything other than the fastest setting is a mystery. There's also full n-key rollover, which means in theory you can push all the keys at once and have each one be recognised by your computer—a feature that's useful for a small subsection of gamers.
Top of the "sounds awesome but is probably pointless" pile has to go to the built-in RGB lighting. Since its introduction by Corsair back in 2014, pretty much every keyboard manufacturer has hopped on the RGB bandwagon and brought out peripherals packed with all manner of flashy lights and gizmos. The trouble is, other than putting on a cool-looking light show, there's been no real practical reason to have RGB lighting. Corsair has tried to make it more useful by offering an SDK to developers, and there are a handful of games that support things like lighting up the F-keys to show how much health you have left.
But for the most part the RGB lighting is there because it looks pretty. Corsair's Utility Engine software allows for all manner of customisations, including custom macros and lighting effects. You can individually light up the WASD keys, for example, or have a wave of light flow across the keyboard when you drop a grenade in Counter-Strike. There's even a mode that lets you use the keyboard as a graphic visualiser when you're listening to music. Thanks to the sheer amount of customisation options, the software isn't always the simplest thing to use, but you can download pre-made profiles from other users over on the Corsair website.
At $169.99/£149.99 for the K70 RGB Rapidfire—and $149.99/£119.99 for the K65 RGB Rapidfire, which ditches the number pad—it's a serious investment. The price is comparable to competing keyboards like Logitech's G810, though, which goes for $159.99/£139.99. The price is somewhat offset by the legendary build quality of the Cherry MX switches Corsair uses, which are rated for 50 million key presses; the Rapidfire will likely outlast your next few gaming PCs.
But for my money, I'd skip the Rapidfire and pick up one of Corsair's other models with more traditional switches like the Cherry MX Brown. They're better to type on, and best of all you can pick one up without the RGB lighting for less money too. The standard K70 goes for about $130/£115—a very reasonable price for a well-reviewed, full-size mechanical keyboard.