If by express heads you mean shooting heads I would recommend the factory made ones. The loop to loop system doesn't shoot through the guides very well, at least in my opinion. I found they hung up where the two loops connected. I think there was a section in Deke Myers book though that explained how to splice a shooting head to a running line. This might go through the guides a lot smoother. I never had the patience to try it. Hope this helps.
-Steve