After going through 4 brand new USB hubs from 4 different manufacturers, I finally found one that works perfect with my mid 2012 Mac Pro! My main issue was after sleeping my Mac, I would randomly loose ports upon waking the computer. This Vantec port Based on the VL812-B2 controller works flawlessly! When I wake the computer even from a deep 10 hour sleep, all ports come back everytime! No more dropped hard drives. all the other hubs had the VL812 chip as well, but not the VL812-B2 with the latest 9095 firmware update, and I think that made all the difference! Anyway, after pulling my hair out, and three returns, just thought I would share. The Hub is made of nice extruded aluminum, and has LED's you can actually see. Totally happy with this product! Now we'll see how long it lasts. Also has a smart 2.1 amp charging port that charges my iPhone 6 Plus very fast.