Yes, I have two of these http://seetron.com/glo416.html
, they use inverse logic.
When using one of them I had no trouble, but when using two of them together, I started getting weird data on the second screen I was using. So after a time of debugging and testing I found out that if the time from the instantiation of the SoftwareSerial and the first write was to long, the data was wrong on the display. The error was that the setTX is actually starting a start bit when using inverse logic, but not the rest of the trasmission.
When using two, both of them was instantiated at the same place, but before the first write to the second screen was done, the first screen was set up, and that took a little time.
So by doing the change i suggested, the setTX does not start a start bit when the SoftwareSerial is initilized.