... crap keycaps, lack of customization...
This combo is a killer for me. If a board has bad keycaps, no worries, just replace them. But you can't "just replace" the keycaps on the K70. You have to live with the crap keycaps it comes with, at least on the bottom row, permanently. Not worth it for some flashy RGB backlighting. Especially considering the complex and poorly written software controlling it.
For more info, read the 1,2 and 3 star reviews here:
http://www.amazon.com/Corsair-Vengeance-Mechanical-Keyboard-CH-9000063-NA/dp/B00KX8OJK6/ref=cm_cr_pr_product_topOh yes, don't forget the poor support from Corsair.
If you just HAVE to have RGB, I'd suggest waiting until other manufacturers release some, I believe the Corsair exclusive deal was only for a year, so other companies will probably start using the RGB Cherry switches soon enough.
If you can live without RGB, I'd much rather get a Ducky for less money. Better support, better keycaps, standard layouts (so good customisability, they even have their own brand thick PBT keycap sets), no software needed, etc.
Like you said, unpolished software. I personally don't like drivers or software for my peripherals. That's why I love the dip switch system on my Ducky. I can control the whole keyboard without downloading software from a website. Hopefully I can find a mouse that will be the same that's good for FPS...
If you're looking for ones with a DPI switch, there are plenty on Amazon to choose from that even support multi-backlighting.
My personal recommendation. Has a lot of good features and more DPI than you'll ever need at a very low price.
I think you misunderstood. DIP switches are Dual-Inline Pin switches. On the Ducky you use them to set up the keyboard so you don't need any software to change anything, it's all done in hardware.
Just to add something to your aluminum > plastic thing. Usually I'm all about aluminum but a friend who had a K70 bought a Ducky (which has a plastic case and a metal plate in it) and he said it felt much better than the Corsair.
Of course this is subjective but I thought that would help you with your decision.
I can attest to this... Came from a K90 and this shine 3 is amazing.
Same here...came from K70 rgb to the Ducky Shine 3 and love it.
You don't miss the RGB backlights?
No don't miss it. It was cool the first few days but it wore off plus the software was so buggy and hard to use. The ducky feels more solid than the corsair and I'm very happy with it.
^^Listen to these people. The Corsair has an aluminium plate, the Ducky has a steel one.