I recently bought Bowers and Wilkins 606 bookshelf speakers anniversary edition and am looking into different AV receivers. The Marantz NR1710 looks like a great option for my current and future wishes (addition of subwoofer, SL and SR), but my main concern is the power. These speakers require at least 30W, according to the manual the NR1710 can provide 50W (8 Ω, 20 Hz - 20 kHz, 2 channel driven, FTC). Would that be a problem when expanding the AV system in the future? Would it be better to bi-amp the speakers?