That device might work but it is not purposed for general audio use. It is a Conversation grade mic for purposes similar to news reporting or interviews so it has a fairly narrow range to reduce noise interference. You may want something more purposed for music or professional grade if your considering making Demos.
I already record (a lot!) i was just using that as a reference point haha. I guess my question should have been: what is the most practical (possible?) way for me to record an audio signal on the transformer.
I can't say all usb mics don't work but there may not be any expressed as supported on an android system. The Transformer does have a 3.5mm Stereo Headphone/Mic combo jack so just about any standard Mic works with an adapter.