usually, depends on the person.... i always drive gentler with my brother in the car, he never used to like it when i had my ford ka and chuked it into corners like a go kart, so now i always drive pretty sedately with him in the car.
same for my mum, she just hates goin fast... she would really like a car with a theodolite instead of a speedometer.
ill maintain being pretty sporty with my dad, he likes going fast, i think thats where i got my like for going fast from. with friends though ill usually be pretty gentle as well, as the driver im responsible for their safety, also i make sure they wear seatbelts.
the only time i really will drive hard, is when im on my own, but definately not to douche bag levels like the nonces who duck an dive around on the motorways overtakig and undertaking, riding bumpers n cutting people up. i drive fast when i like, but always safe with idicated sure footed moves.
thing is with passengers.... you know when your about brake hard, or take a corner fast...you're prepared for that, but passengers arent. theyre usually not watching what your doing or where your going very much. also passengers tend to want to talk to you so your attention is somewhat divided.