I've been taking my 2000 BMW 528i to Kassel for a couple of years.
They have kept my car running smoothly, and the customer service has been excellent.
I've mostly dealt with Randle who can be recognized by the impressive red beard that he sports. He and everyone else at Kassel have always been very courteous, professional, and up front with the expected cost of service and repairs.
I have had no complaints about their work.
Give Kassel a try.