Yes, the Olympus ME-30W Conference Kit microphones record great with normal conversation volume levels whether or not they were directed at the speaker or away and up close or 10ft away. It will work with the default settings on the Olympus DM620 or you can adjust the microphone levels to preference. You are also able to isolate the different channels (Left/Right) using the Olympus AS-5000 Transcription software, which can be handy if there are two distinct groups in the conference.
NOTE: This combination would be an ideal conference recording solution for users working in a MAC environment.
Verification Source: In house testing
Test Date: 1.13.12