I'm not convinced you need gaming or mechanical keyboard to be good.
I use an old wireless kb/mouse from logitech. I have no problem stomping pubs at top 1 percentile.
And I used plain old cheap wired mouse to play CS and maintain 2.5:1 ratio consistently.
I think this whole 'gaming mouse/kb' is largely marketing to make $$$. They sure have their benefit though, but not worth the cost.
Aren't you Asian? You could have your hands tied behind your back and still outperform most of us normal folk in most games.
For some games, keyboard doesn't matter at all. For some games, keyboards make all the difference in those that can play said game competitively (or, for someone who is mostly "there" but not quite, a keyboard might make all the difference - it won't change your game unless your game is currently limited by it. sometimes you can tell, sometimes you can't).
For some games, it doesn't necessarily have an impact, but it can depending upon your exact play style. Are you likely to use certain key combinations or rapidly roll from certain keys into the next? KRO (key rollover), how many keys can be pressed at once (and if it's the entire keyboard, or only certain key combinations), will be detrimental to some, largely unimportant for many.
I found, even in Battlefield games, that the way I approached certain key clusters, and what keys I tended to use at the same time, on a few different keyboards introduced different issues. I had KRO issues (too many keys pressed at once on a particular board), and I also had bad switch issues, where I might not have pressed a key fully, or didn't let it travel up enough before rapidly clicking again. If you ever feel like any key press is ignored, it is almost guaranteed not to be a game glitch (some view these moments as such), but rather a keyboard error, a missed key activation.
I went mechanical for those reasons, and for the superior tactile response for daily typing. Best of both worlds.
I have a Razor Blackwidow Ultimate Stealth (2012? original edition). If I was buying a keyboard now, and wanted it made by a large accessory manufacturer (importing those various boards, like Ducky and whatnot, is not everyone's cup of tea), I'd probably pick up Logitech's mechanical keyboard (with the same Cherry MX Brown's as my keyboard right now).
There's a wealth of information out there about the different switches and whatnot, that I had not previously known about before researching mechanical boards before my first purchase. Some incredibly detailed information - easy to find by searching "difference between cherry mx switches" and "mechanical vs scissor switch vs rubber domes" to get a good broad overview.
