Some of my students assembly on the LM324 Blink Kit. This is the same project I did back in July 2011 http://www.n1ir.com/2011/07/10000-lm324-donated.html . So far we have 100 kits assembled in about 2 hours, milling the PCB take considerably longer, about 18 hours. Total cost of each kit is about $0.50 a big cost savings. Way cheaper that the $3.00 kits we were getting.