Found this with a quick google search -
"Question - If I rollover a Maryland 529 account to another state's 529 program, does the state of Maryland recapture any of the state tax deductions I've received in the past?
Response from the College Savings Plans of Maryland - Currently they do not. There may be a recapture provision in the event of a refund, but not if the funds are rolled over to another states 529 plan."http://www.collegesavingsmd.org/post-a-question.aspx
You might be able to get the best of both worlds. Contribute to the MD plan, get the tax benefit, then roll into a better plan.
Retirement investing is a marathon.