Product review (1 stars): Great looking but not very effective
Like another reviewer, I purchased this item for its looks and supposed 840 CFM fan, but besides not adequately fitting a 8ft ceiling without some modifications (unit can only be mounted at minimum recommended height), it does not work as expected.  It barely sucks up any smoke, except perhaps any coming from burners directly below the inlets.  Smoke from burners in the periphery mostly goes around the hood.  I don't think this unit is truly sucking air at the rated CFM, or if it is, it perhaps does so only without the charcoal filters (i.e., venting unit to outside).

The expanding drywall mounting hangers provided are practically useless since the screws provided for them are so large that when attempting to screw them into the hangers, the latter loosen their hold on the ceiling and then just spin.  I had to use 4 heavier duty anchor butterfly type hangers instead of the provided hardware.  Even then, I'm afraid that an inadvertent bump on the unit could send it crashing down (ergo: should really install wood braces between the ceiling joists and hang from those instead).

Another problem is the recommended height, which is listed as 650mm to 700mm off the cooktop.  That is roughly 25.5 to 27.5 inches.  Even at the higher limit, but, of course, more so at the lower height, the angled glass ends are just low enough to hit you on the head when approaching the cooktop if such is not far into the island (more than 4 or 5 inches), which ours is not.  Thus, until we raise the unit to a safer height, which we plan to do with much dreaded, needed adjustments, we need to be careful!

Although the unit looks great, I'm very disappointed with its lack of practical performance, which is not any better than my old, cheap, over-the-stove vent fan. I will be contacting the vendor to inquire on what could be wrong or see if they offer to replace the fan, or what.  Stay tuned...

One final note.  The unit comes with a charcoal filter for inside venting, but not being completely sure of this (the description wasn't clear on it), I ordered one separately.  However, it seems like the vendor tried to pull a fast one on me by not initially shipping the additional filter purchased with the excuse that they "some times put it inside the box," which seems like a lot of hogwash since the unit had a spot in the packaging for the filter and the box was sealed.