"...ignorant newbie post"? I don't think so!
The great thing about the theremin is that unlike traditional instruments, there is no established way to play it, no "right" or "wrong", and no particular sound or tone that is considered to be the universal "gold standard" for the instrument.
If you like the Burns B3, go with it.
The music that you will ultimately create will appeal to people who like what you like. The more obscure your musical taste, the smaller your audience will be.
Like many newbies, if you stick with the instrument, you will eventually graduate to a more sophisticated theremin and your next choice will be an informed one - but you have to start somewhere.
There is a fairly high dropout rate for the theremin because people who want to play with precision quickly discover that is an extremely difficult task. People who want to play SciFi & noise FX often tire of the instrument after a few weeks because there are other much simpler ways to do the same thing with far greater variety and choice.
Clara Rockmore said that the most important single thing for beginner thereminists is for them to know exactly where they want to go before they start. This will determine the kind of theremin they choose, and the technique they decide on to play the instrument. Most people assume that they don't need a method in order to play because the basic principle is so simple they can just "wing it" and do whatever feels right. That will work fine for some kinds of music, but not if you want to play like Clara.
The theremin is a one-trick pony but that trick, if you can pull it off, is unique in the world of instrumental music.