I use that same device on my X60s and my X230, both without issues. I did have one of those devices seemingly give up the ghost on me, and but the two that I have now get used all day everyday and have been just fine for more than a year.
I seem to recall Chris (the CEO of ThinkPenguin) saying that there was some USB power issue on some machines; I don't remember when he mentioned this though, it could have been right around when ThinkPenguin started selling them. You might ask him, or @jxself@identi.ca who I think played a role in packaging up the free driver.