Whether or not you are happy to put a child in the front seat without turning off the airbags depends on many things. I wouldn't as the car will be a daily driver and so 7 year old son will be in it every day. I might have however if it were only occasionally. My first call was to the Milton Keynes Safety Centre - they are REALLY good on this stuff. They told me that it depends on individual manufacturers and what they recommend. BMW says you must deactivate and given that booster seats boost a child forward as well as upward, I would, personally, not take the chance on a daily basis. I may be over cautious but I'm a worrier and I drive on twisty back roads where everyone seems to drive like they stole it. It's a personal thing, but husband and I decided that it was safety first for us.