Product review (4 stars): very nice after tweaking.
finally got to install the product, it does work as described.  good suction, but not much difference between low and high fan speed.  wish the low setting was a little more quieter.
also when i first got the hood installed, i had some intermittent low grinding noise from one of the fans.  and when i looked into it, the plastic circular oil catcher had some screws backed off.  however when i tighten the screws, the grinding noise came back constantly and louder!  so that tells me that quality control at the manufacturing plant did shotty work.  however after a couple hours of trouble shooting and altercation to make the grinding noise go away, i do like the fan especially the price i paid for it!
for the unlucky people that gets the grinding noise ones, it's not the screws that causing it.  mine was the center lip of the plastic oil catcher.  after sanding down a few millimeters and made a clearance, the thing works great!