Bottom line about any comparison with headsets used by big stars...

Ask them what the FOH guy uses for pre-amp, EQ, compression and gating to get them to sound so good. And how much that FOH guy charges a night!

The mike is only the START of the chain.

Most modern big shows, the star rarely gets in front of the speakers, and they all use in-ear monitors, so feedback is rarely an issue. I think that's the big difference. No in-ears, big issues...
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An arranger is just a tool. What matters is what you build with it..!