I saw some talk about the tires machines on a Automotive technicians forum and they said they're junk.
I have no personal experience with them, but there are a lot of other people who chimed in saying the same.
You get what you pay for, I guess keep that in mind.
If it's something you use once in a while, it might be ok to go with, but if it is a tool for a somewhat busy shop, I might look at other proven options.