Well I was doing some research on the ABS/PVC thing. Check out this post
http://www.reefcentral.com/vbulletin...001/10/4/35413
From this discussion ( and a few other spot) there are two issues to consider. The first is pressure. PVC can handle higher presure and as such is a better choice of supply tubing. Also the choice of solvent/glue can make a potable pipe non-potpable..in PVC and ABS. So you can use a potable flexible PVC pipe...but the glue makes it non potable and you can use a potable ABS pipe with the wrong glue and the result is the same.
It appears that both pipes are potable..but check out the glues..