IIRC (five years have passed) ATR 42-300 with PW120 and Hamilton 14SF5 four bladed props used 100% for takeoff and approach, 86% detent for climb and 77% for cruise when out of icing conditions, 100% being 1200 RPM. We could set RPM anywhere between detents and often used 92% for cruise in icing conditions as it was less noisy than 86%, increase in consumption was minuscule and cruise speed (250 KTAS) not affected.