The bottom line with using the Dragon speech recognition system in a Special Education setting is this:
Make sure it is a better option than what your students are currently using, and that it is worth the price tag. If it meets your students' needs and offers them independence and the ability to communicate electronically with freedom and confidence - go for it! If it creates frustration, distress or anger, or causes families to feel they too have to part with valuable household funds to buy a home version of the program, think again. There are other options (scribing, using a head pointer, using scrolling text on a screen) which can be more suited to the needs of some students.