There may be different level of proficiency, however both are still considerably good in their specialty. After all, it is "fan-subbed" and people who are doing the scans are volunteers. They could have studied the Japanese language to a certain level (how high, I have no idea), forking out their time and making an effort to do it. Unlike those who work as a Translator who require at least an academic certificate like a Diploma or a Bachelor Degree, or higher. Some of them also teach and write books. Therefore, I am quite happy with the various groups and individuals in doing such work.