Here are a few recommended shops in your area; the last link is a full list of independents if you want more options:

http://www.baltimore-bimmer.com

http://www.autowerkesinc.com
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Welcome! Great to have you on-board.

Was the thermostat and/or water pump changed during the 100k miles service?

I'd also wouldn't drive it at all if it ever starts overheating. You easily...