I had Al Hafner Tuning work on my 2002 M3 more than once over the past two years. I generally had a difficult time getting anyone to answer the phone during both service occassions and great difficulty in receiving a timely return phone call when I left a message, especially the last time (Jan. 2011). Upon my arrival home with the car the last time they serviced my M3, I found I was over charged on a $1300 invoice based on what they had advertised that month. I left 4 messages over 7 days and did not receive a return call from the service manager until the next week. They had left off a previously discussed 10% discount on the invoice because I forgot to give them a printed version of a coupon off their wesite (which was not a requirement - per the offer). The matter was never resolved. They have a clean orderly shop and seem to provide competent workmanship, but have poorly managed customer service and rather rude telephone etiquette in my two experiences in 2011 and 2010.