I've just bought a Gutmann Abajo with 2 induction hobs and the extractor in-between. It's not been delivered yet, but is proving a nightmare. You can only buy it through a recognised Blanco dealer, which I did, but they had never even heard of the Abajo and it took a week to get a quote. They said get in touch with the tech guys for tech help about installation, but they refer you back to your kitchen planner. Our kitchen planner is building our kitchen, but he won't be up to date with putting in a ducting system. The real problem is we want it on an island and the ducting to go underground to the until just inside the outside wall when it can come back up in a cupboard and be vented out through the wall. Bora have a section about putting it under the floor- Gutmann have nothing. Bora says putting under the floor can be done in certain conditions, and has reinforcement to withstand loads- Gutmann doesn't. Apparently the bends we need to put in will lose 20 pascals(?)Tech guy suggests boxing in the plastic ducting to protect it from weight. With a vertical joint taking the ducting down, and another taking it horizontal, it looks like it would end up about 180mm below the floor. I wish I'd gone with Bora now. Has anyone dealt with underfloor ducting before?