Product review (4 stars): The contrarian opinion
Well, after seeing the other terrible reviews of this product, without apparent consideration for how it actually FUNCTIONS, I wanted to add my experience.  Our fan was installed 1 year ago with a gas cooktop, and we have been very happy with the function of the fan so far.  If you measure before you purchase, there shouldn't be any problems with the top striking cabinets, blowing fuses, etc.  We did have to make some adjustments under the cooktop as the fan was quite a bit bigger than the original, but it wasn't difficult.  The fan is powerful, and rises high enough to be effective in ventilating all 5 of the burners.  The elevator works well enough, though we usually leave it in the up position, as my wife is always making stinky things that require serious ventilation!  The only problem we've encountered is that the filter surfaces (they're both removable and dishwasher-safe) are fairly easily scratched.  The scratches are superficial, and I haven't tried buffing them out, but they are very noticeable.  If you leave the vent up, and keep your stove empty, they're easy to see.  Usually there's something blocking the view, so we don't even see them; they're only cosmetic.

Again -- great functioning powerful fan, and very happy so far!