on my S200 there are actually 2 places where you can drain the oil from...the actual drain bolt (on left side, but will make a mess when it drains, as it drains onto something that I can't quite recall right now) or the bigger bolt which contains the oil screen on the right side of engine. I drain from the big one that contains the oil screen. Needs to be checked and cleaned, anyway.
Wonder if the X300i has a similar setup?