Speaking of the different models and ways to construct a Talk Box, I have a Rocktron Banshee 2. This is far better than the original models in that it acts like a stomp box. Where with the other models you need to have separate speakers, and almost an adiditional rig of gear just for the talkbox. With the Rocktron, it can be put in line with your other stomps. How it works is when you engage the unit it actively sends your signal through the tube and you are ready to use. When disengaged, the unit bypasses the tube and pushes the dry signal through your stomps and into your amp as normal. It's the best version of the idea I have seen.

Another feature I like about the Rocktron is that it also contains its own volume, gain and tone, so you do not need to redesign any of your other stomps to boost the signal when using the Box.