Hi Kelo,
Welcome to the forum and to the Pleione obsession! If you post pictures of any of your "mix" when they flower, we can try to identify them for you. Some are distinctive so are easily named, while many hybrids are so similar to each other that it can be impossible to be sure what un-named plants are. We will do our best.
Perchance you are not aware of my Pleione Website, that is a good place to start for cultivation advice - see
www.pleione.info - and we can try to answer specific questions here.
I am unfamiliar with "Mei Moon" - it is not a registered name. Do you know any more about it? You may be interested to know that 'Cairngorm ' and 'Oriental Splendour' are named forms of Pleione formosana, while 'Gary Mundey' should be Gerry Mundey and pleionoides Yunnan should be bulbocodioides 'Yunnan'. Hope you dont mind me pointing these out - if you are not bothered about proper names, just ignore me and enjoy the plants!!
Paul