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I don't know what your assumptions are, but I don't think the 4070s are inferior to the O2s. My order of ranking is SR-Omega > 4070 > O2. People don't like the 4070s for various reasons, such as weight, closed backs, too bright, etc, but the reality is not that many people have even heard them, and even fewer have heard them side by side by side with the two Omegas on an amp good enough to drive them all well.