Check around a little before going T8s, some areas of the US government are trying to get ride of them.
From a random article on the web, from what I know it appears correct enough to get the basics across.
"DOE is regulating T12 lamps and some T8 lamps, incandescent lamps, and other inefficient technologies as a method of moving energy consumers to be more efficient. The new standards for linear fluorescent lamps is based on efficacy, or ensuring that newer lighting technology offers greater lumens (light output) per watt and a higher CRI (Color Rendering Index.) In effect since July 2012, the legislation eliminates nearly all 4-foot T12 lamps, some 4-foot T8 lamps, most 8-foot T12 lamps, and almost all standard halogen PAR38, PAR30 and PAR20 lamps from the market."