It does matter a small amount that the 61 and 62 use the same midrange drivers, because they will be more closely timbre matched. The 81 will outperform the 61 due to the 97dB sensitivity vs 95. +3dB is a 50% increase in sound level and +2dB will still be meaningful, however that does not mean one will sound better than the other based on that alone. Between the 61 and 81, I would go listen to the two and decide which sounds better to you.