Whoa now, Lazo wants to say the experiment isn't useful because it uses undergrads who may not represent the actual demographic of interest? Does he want to abandon human-subject experiments altogether?
Abandoning the inexpensive-but-heavily-skewed "grab some of the local population" (of our university town) (in the Western world) wouldn't be a bad idea for psychology, no.
http://www.scientificamerican.com/podcast/episode/psychology...