I barely know any Deaf people who still use a TTY. Why keep a TTY anyway? Baduot is so slow, and you have to use "GA". A Hard-of-Hearing friend of mine got DSL and a videophone. I recently told him to ditch his TTY and get a CapTel. He traded his TTY in for a CapTel with his state's program. He absolutely loves it. He doesn't have to use "Go Ahead", and he can use STS (Speech-to-Speech) relay, for Hearing people who do not understand his voice. He can also be rest assured that he can access 911 quickly in case of an emergency, with his voice, rather than type on a TTY. He can also call his Deaf friends, who still use TTY, with relay, so it's not like he gave up anything.
CapTel also gives him freedom from difficult English. My friend knows ASL better than English, so if he reads something he doesn't understand, he turns his videophone off, and then he uses his CapTel to call himself with VRS. The interpreter says, "The person you're calling doesn't seem to be answering the videophone. Would you like to leave a video message?" He then leaves himself a message, and then he checks his e-mail to see what the message is in ASL. Getting that kind of freedom is impossible with a TTY.