What about Masd. exquisita, nidifica, and herradurae?
 

I have just ordered these Masdevallia. All of them will be mounted. I've never had any luck previously with Masdevallia, I'm determined to try again. If anyone has grown these Masdies, please let me know your thoughts. Thanks.

I have herradurae, and I grow in intermediate/warm conditions. No problems at all with its culture; it has bloomed really well twice a year for me with very little care. I grow mine in straight sphagnum moss in a slotted pot, watering when the surface of the moss starts to feel dry. Good luck!