c43amg- Jackie Cooper is great. I'd definatly recomend them over any indie mechanic I've gone to, even thought they can be rather expensive. They've even serviced my car on saterday just so I'd have it for the weekend. The service department is wonderful, they actually know me and my family by name.
My family has bought five new cars from them, and haven't had a complaint. I haven't had any experience with their used car department, but I'd expect the same.
As far as indie mechanics go, I could recomend Fritz (I don't know his last name) who owns Automobil Sales at 111th and Memorial. I bought my car from him ('88 420SEL) with 120k and it's perfect. He does great service. Email me and I'll give you his phone number and address.
Do you actually own a C43? I've never seen an AMG car in Tulsa other than a ML55 a week ago at Home Depot.