Price has been the biggest reason for me. I just think Bosch makes a better injector as well, though. Maybe that is just a gut feeling. I have gone 150K miles on the same injectors and they are Lucus. I guess Lucus injectors can't be all that bad. But 250-275 for a set of eight... hmmm
Take a look at this site...
http://www.fiveomotorsport.com/