I have been running the AMD-pro 16.60 and optiminer 1.6.2 for a week on one rig without problems. I have had several GPU's drop on rigs with AMD-pro 16.50 drivers so I have updated all to AMD 16.60 and optiminer 1.6.2.
320 S/s on XFX RX 480 8GB cards
310 S/s on Nitro Sapphire RX 480 8GB cards
7 GPU's 1130 Watts at the wall
The XFX cards are slightly more unstable but worth the higher hash rate.