i didnt bother to read through all the responses but from what i know you CAN run it lower than recomended octance, you just cant rag the engine out. if your just crusin along from work and back, not racing or pushing the car, then you'll be fine. but if you wanna have some fun with the car, then put in the recomended octane.
oh, and dont forget to push it once in a while to dump your carbon build up