I use the lead free leaders, I make em up at home so I can swap em over quickly.. they have a small loop in the leader at the mono end and the lead slides nicely over end, so are quite safe... l got em off the bay... think there were 10 for £12 posted...
I use light leads of 1.5oz max with small bags as I don't want to overstress my cane rods on the chuck... as a system I find they work well... just gotta buy more 1.5 and 1oz leads to make up a batch of bags per session...