The ability to create your own models is very important to use this, as your existing ones do a bad job of processing my normal speech. To test I just tried reading a few simple phrases and the error rate is pretty high. The Web Speech API did a great job with the same phrases https://www.google.com/intl/en/chrome/demos/speech.html
It is understandable; different people may see different performance depending on what speech service is used. In addition, please keep in mind this is just a beta service; we have only been out there less than a week and know we still have some tuning to do. We also recognize the need for customization and personalization abilities; keep watching our website for continuing developments.