Here's some data
http://www.tomshardware.com/forum/id-2791401/xeon-1231v3-haswells-synthetic-benchmarks-science-fair.html
I might do a lot of things, but putting a K chip in a H motherboard is not one of them.
You are paying more for unlockability, the chip is no faster, and overclocking has limited value in gaming.
I would put a locked chip in a Z board sometimes, because then I might be able to later SLI two GPUs, and I can use faster 2400Mhz memory, which will also have a small increase in gaming performance, but at quite modest cost.
Your Operating System will be keyed to your motherboard, so a motherboard change later is something to avoid.
I do disagree with this
get 4590+H97+ SSD [for OS & Games] it will give you better performance than Z97+4690K however, I have the data to show it is not so. In most gaming, that performance is not cost effective, and having a SSD WILL make your system feel faster. A ten second boot gives more game playing time
For the i5 series, it is all about Megahertz per Dollar (divide the Speed in Megahertz of the Turbo Boost frequency by the cost in your currency) The CPU with the highest number is the most cost effective. The cost effectiveness of K chips is reduced by the more expensive motherboard and aftermarket cooler.
An i5 4460 or 4590 is plenty. If you are doing things other than gaming and you have a discrete GPU, then the Xeon 1231v3 is worth thinking about.