Several single-walled carbon nanotubes (SWCNTs) prepared by different methods have been used to investigate the material dependence on the optimal film performance of flexible transparent conducting films. The nanotubes were dispersed in water with sodium dodecyl sulfonate by sonication. These SWCNT solutions were then sprayed onto the polyethylene terephthalate substrate by a spray coater to form the film. Several factors such as purity, diameter, defects, metallicity, and degree of dispersion were evaluated individually to examine how they affected the film performance. We found that the metallicity of SWCNTs and the degree of dispersion are the most crucial factors in determining the film performance. We also proposed a material quality factor to estimate the material quality of SWCNTs as a figure of merit for the film performance.