I have a couple of forms of E.epsteinii. This one has paler brown/purple petals and seems to be taller growing (so far).
This excellent form came from Wendy Perry at Bosvigo House in Truro. Very beautiful dark purple petals concealed from above by the broad white sepals. The species was collected in Hunnan in 1994
for Beijing Botanic Garden, thence to Darell Probst in the USA. The name was published in 1997.