I went to the June Savannah, GA GTG in 2009 - and bought a Roadster less than two weeks later.
Since then, I've on been to the Dragon GTG:
Fall 2009, Fall 2011, Spring 2012, Fall 2012
I was at the Spring 2010 one, for about 3 hours
and I THINK I was at the Fall 2010 one as well...