good keyboard?

IMO not a big deal just as long as it's comfortable.

that's too slim for gaming...
for example when u doing b hop.... u might touch other key pads by incident!!
i have logitech g15 keyboard..

Best thing to do is go to a store and try them out.
Arc is very slim, not at all suited for gaming, although its cute.

If you're looking at Microsoft specifically, get an X4.

Buy one that has a key buffer of about 5. So you can press 5 buttons at once and have them all register.

The G15 lets you press 4 keys at once. For instance if I press ASDF and hold it, it will repeat in that order:

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