Well, i personally can't stand the look of TE tin (i'm sorry lemmy D: I just can't), so i enable IC copper and tin generation instead. These work perfectly fine in the smeltery.
Actually, I think he meant to say TE specific ores (e.g. silver and lead). TE copper and tin work fine in the smeltery (since they're ore-dictionary equivalent to TC copper and tin). If anyone's curious, I asked mDiyo in his thread about that, and he responded that the smeltery has an api that allows the mod author to allow their ores to work within it. So TE silver/lead could work in the smeltery in the future, should KingLemming decide to allow it.