Re: Mechanical keyboard
any keyboard that uses Cherry MX switches is going to be fine. IMHO they are more reliable than traditional keyboards that use membrane switches, and most reputable brands such as Corsair and CMStorm ensure good build quality.
the K70 is a good keyboard - but do some research into different types of switches and decide what kind of mechanical switch would best suit you. Each different colour (e.g. Cherry MX Red, MX Brown and so on) represents a different actuation pressure (by that, I mean the pressure you need to apply to the key for it to register the key being pressed).
I've got a Razer Blackwidow, which uses Razer's own switch design that has a medium to heavy actuation, which is good for gaming because it's hard to accidentally hit a wrong key, but it's tough on the fingers for long typing tasks.
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