There really aren't any bad seats at the Birchmere. Get there early to get the better seats though, or you might be looking at one musician's left eye and ear for the entire performance. The food is high-quality "bar food" at reasonable prices. Ticket sales have been contracted out to Ticketmaster, so add ~15% to the quoted price, even if you come to the window. Concerts almost always start promptly, and most performers will stick around to autograph CDs.
Hint--RT's Restaurant, right across the street, doesn't look like much, but they serve excellent New Orleans cuisine. Save it for a different trip though.
My chief gripe about the Birchmere is that they can sell out a major act on on a weeknight, so they tend to have obscure acts on weekends.
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