Here are the specs for Mike's Meadowlark Audio Osprey:
Bandwidth: 30Hz - 24KHz
Sensitivity: 88dB 2.83V 1M room.
Nominal Z: 8 ohms
It seems that his request for 120-150 wpc should be plenty of power, depending on room size and listening levels. Assuming he has a moderate to large size room, and listens at moderate to loud levels, he should be fine.
He would only need more power if in a VERY large room, and/or listening levels are concert hall levels. IMHO.