I think that Pete of Surgical strike fame, along with possibly a few others might be using the cheaper units, but I guess that a lot of it has to do with what you are going to use it for.
I haven't really looked at all the features, but in my case, I need to be able to switch betwen multiple models, or i wold be dead in the water. But all I do is R & D on multiple bots, so your needs may be drastically different.
Best to do a lot of research before switching and regretting. If this is your first transmitter setup, you might want to keep what you have...it's kind of a proven product for robotics application.