For gaming, it's like a heavier black MX with smother action and less key wobble. The extra force will only really bother at the second half of travel (at least with heavier double-shots).
It's not recommended for typing, but imho it's easier to avoid bottoming out than with MX blacks, simply because you can't do it with the same light touch (crazy ~110g at the end of travel, two springs) and doing so will get you tired quickly, so you adapt in no time (for the wrong reason).
To rephrase it, avoid G81 when in doubt. It has that feeling of something made to outlast you, but not to be comfortable.
(I like them a lot)