I really like the Corsair Vengeance M90 mouse and the K90 keyboard. They are both great pieces of hardware that will last you a long time. They are both stylish (without being overdone or garish), a pleasure to use, and built like tanks. They aren't perfect. But what is?
The best thing about the issues present are that they are easily overcome, or can be fixed in the future. The biggest issue is the initial user experience. Neither product comes with documentation on how to use the Vengeance Gaming Software for configuring macros. The information is available from the Corsair website in the form of a PDF guide and screencasts. However, the information is much harder to find than it needs to be.
Once you get a handle on using the software, things turn around. Any issues with software functionality can always be addressed in future updates, and Corsair has a pretty vibrant forum community that is helpful.
The real lynch pin in looking at the value proposition of the Corsair Vengeance is the hardware. No software update can fix poorly designed or constructed hardware. Good news is that both the M90 mouse and the K90 keyboard are exceptional pieces of hardware.
If you're looking for a mechanical keyboard and/or programmable mouse, then this pair from Corsair deserves your attention. The main reason I don't give the 90-series our "Highly Recommended" award is that a mechanical keyboard just isn't for everyone. For us to "highly" recommend something, it really needs to be something that any gamer would enjoy. Like a gold seal for multi-monitor support on a game, you should be able to pick it up without any worries.
If you're more of an FPS player, or are looking for something a bit simpler/cheaper, then check out the M60/K60 pair. Everything I've said in the review (from a hardware perspective) applies to them. They will give you the same great performance for about $25 less (for the pair, on Amazon). If you're into any sort of strategy or role-playing games (single-player or MMO), then the 90-series will serve you well.
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