Speech Recognition/Dictation on Windows 8

Windows comes with built-in speech recognition since Windows Vista. It's utterly unusable. Here are the main drawbacks:

• I can't interact with other programs while this thing is active. It somehow intercepts UI events, or maybe it just runs with such a high priority, that other programs don't get to update. Either way, it grinds my PC down to a halt.
• After half an hour I have up on dictating/spelling an "@", which I need for such exotic things such as dictating an email. I don't have the faintest idea how this might work.
• The help section is pretty useless. It keeps promising to show an "Interaction Card" or something like it, but instead opens a browser window that shows me Videos on what speech recognition can do. The videos are in English, my system is in German, so that doesn't help me at all. I gave up on using it. I wish Microsoft would have the balls to yank out unusable features - instead, the Windows install is ballooned to tens of GB with crap like this.