Hey those 18's look REALLY good - and its nice to see how well the M3 bumper works as well. Having just bought the wheels, I will have to hang off getting the bumper for a couple of months I think.
I prefer the standard suspension - mine had been lowered when I bought it, so I had it returned to standard.... it handles better with standard. I had the BMW centre tell me that you can never get the wheel alignment spot on with lowered suspension as one of the three things they adjust is set by suspension height on a BMW.
Not only that, but you drive a car with lowered suspension here (and wheels more than 2" over stock) The cops will defect it and take it off the road until suspension is corrected and wheels are no more than 2" over stock. Can be a very expensive exercise.... I should know, beings I am a cop, I have taken HUNDREDS of lowered Commodores off the road. We are shown how to measure eyebrow height from centre of wheel to top of wheel arch and we have a huge book of heights and wheel sizes for every make and model of car that wears an Australian Design Regs compliance plate.
Don't even bother driving a car that doesn't have an ADR Compliance plate......
Did you check out the thread on the Nology Hotwires?