I have 4 used TPMS units out of an 07. These came in a set of OEM wheels/tires I bought, but I have an 06 so I never used them. They worked when I bought them three years ago, but I haven't used them since, and I have no way to test them, again since I have an 06.
Three of them are missing the valve stem center, which I'm assuming you replace when you install these in new wheels.
Unknown battery condition, but hey, you're getting 4 BMW oem sensors for $20 shipped.