Greg, is your friend registered with the MS society? They have all types of grants available for their members and if this sort of aid doesn't qualify I'd like to know what does!
They could have been asked for this before and may well offer advice on the best program to get, however, the phrase "horses for courses" may well apply and what works for one person may not for another.
If all else fails I have an old copy of a voice recog. prog. (somewhere!) which I could dig out and send, it was a freebie with something about 18 months ago so it's probably not leading edge.