I can see the difficulty you would be havin' bow, without a PA to run it through. If all you got is the box into a mike into a sound card then it is gonna sound kinda' thin, depending on what your monitoring system consists of.
As I recall when you kick on the talk box it cuts out your guitar speakers then sends the signal to the horn, up through the tube. If you can figure out a way to beef up your microphone sound you should be able to beef up your talk box sound as well.