VGA is outdated, and DVI/HDMI are better equipped to handle higher resolutions. VGA is an analog signal. HDMI is a digital signal. There is much greater risk for signal degradation, particularly with a long cable, with VGA than HDMI.
Mini Display, same set up I am using with my 2007 BMB hooked up to an ergonomic arm. When the BMB dies, (if ever), I will mount a 27" ACD on the arm and use it with the 11" MBA, for now the MBA and my iPad are my couch buddies, (along with my 18 month old Chocolate lab Reilly)😎