I purchased diamond wax apple and green wax apple from them before.
The trees were healthy, but have small root system.
Both trees were about 12-18" tall, I paid $50 for each
Wax apple is very cold sensitive especially when it is young. I killed both of mine because the temperature went below 50 degree at night.
In case you decided to purchase it, you need to keep it indoor or in a green house.