All the G80's are MX right? so they should be "mx compatible" by default. I haven't used any, but especially given the success of Quarzec's Cherry doubleshot groupbuy, I would say that the Cherry G81 (MY) should also be compatible.
Ripster's right: this information is in the wiki, though he's not nice enough to provide a link. I've always found the title of the wiki articles to be rather confusing.
Now here's the problem: a lot of older 'boards may work on the A-Z keys, but modifiers may be an issue. This is certainly true with WYSE
The cherry switch wiki gives some examples, but I notice they all seem to be modern keyboards.
http://geekhack.org/showwiki.php?title=Cherry+Corporation+Switch+WikiGiven the relative ease of keycap pulling, and the instantly-recognisable cherry cruciform, you may just want to instruct relatives in this art.
Although you may still end up with some oddballs. looking in the vintage switch wiki has pictures:
http://geekhack.org/showwiki.php?title=Identify+That+Vintage+Switch+-+The+Geekhack+Switch+Reference+WikiFor example: BTC, datanetics, chiconey, Marquardt, MEI, NEC (maybe futaba, seijin)
I think I read somewhere that the Marquardt ones are cherry compatible, some of those others may be as well, but I can definitely see the stems looking similar, which confuses things.
There is some sort of cherry product number-wiki, but I remember it being confusing.
I would also like to say that I notice the cherry section of the vintage switch wiki is "outsourced" to another article, which is currently not available. This is likely the reason Ripster didn't win that DT poll. Likewise, the "OTD" entry consists of a deleted GH attachment.
It's things like this that prove he's not the #1 wiki-maintainer on the planet. The jury's still out on "keyboard expert", ofcourse.