the aluminum finned copper tubing should be fine, just if it is going to be used for hot water in your house (showers, sink, etc) I would make sure there is no lead used anywhere on it. Lead poisoning is bad news. But so long as its lead free and rinsed out a few times and no other toxic chemicals/metals in it, it should be fine.
If you are on the other hand just using it for radiant floor heating not for showering or any other direct human or pet contact, then it really wouldn't matter as much, even an old radiator (leak free of course) would be alright, just don't want to have toxic chem's used where people will be exposed.