Uticor, AVG, EZAutomation - explosion-proof
I've used both the older PGI100 from AVG/Uticor and the newer EZPanels from AVG/EZAutomation. I prefer them over the A-B products because you don't need to compile the program and download it (not to mention the lower cost). You also can upload an existing program from the display and do online editing.
The PGI100 was one of the first DH+ displays to have the Class I, Division 2 (not explosion-proof) rating for the US which was what I needed for refineries and pipeline stations.