I would go with ABS for this.
Hopefully I won't end up more confused than I already am.
I my basement, I have a 3" toilet drain in my concrete slab. It's ABS. I'm installing a sub floor over the slab and afterwards, ceramic tiles, then a toilet. My question is, should I use an ABS flange, or a lead one (with an ABS sleave which slides into the drain pipe) and brass ring? Some say to go with ABS, since it's easy to work with and lead is not, wihle one plumber at the hardware store suggested me to use lead, because if the floor moves just a little, the ABS will crack and since lead is soft, there's no problem.
I really appreaciate your help on this.