Would you choose a degree qualified non-native English speaker in teaching and linguistic over a native English speaker with no academic qualification? If your purpose is to ace in academic field that demands rigorous grammatical correctness, proper choice of words and structure, then a degree qualified non-native English speaker is fine. If however, your purpose is to aim English mastery as an active medium of communication in daily life e.g. speaking and listening, then nothing substitutes a close contact with native speakers.
