We're having an induction hob (90cm) on the kitchen island in a brand new extension. I like the look of the ceiling extractor I have linked above but worry about how efficient it would be compared to a chimney hood which I presume would hang lower down so closer to the hob.
I don't know the ceiling height as yet over the hob but it will be a sloping ceiling so some sort of housing will need to be built for the ceiling extractor if I went for that.
they don't sit in the ceiling completely, unless a single story room as the motors are approx 30cm high. they are effective and creates more visual space. Check what direct your joists run to see if your able to duct out to an outside wall
there are a bit more powerful to make up for the extra distance they are above the hob. they will work to the same effectiveness as a normal island. easy way to find out is to call the company your interested in for the extractor and speak to there tech department.