Okay switching this to an answer.
As you mentioned PSM I and PSM II have the same subject matter and syllabus, and with the recent change to PSM II it does not have essay questions any longer.
The difference in the questions is PSM I has fairly straightforward questions with textbook answers, ie if you read through the material you should be able to pick the right answers out of the multiple choice.
PSM II is meant to have harder, more situational questions showing you understand the application of Scrum in a real life setting, rather than just knowing the principles. From the material I read when taking PSM I ( I have not taken PSM II) they expected someone to have been a Scrum Master for a while (or take their course I suppose) to do well on PSM II.
A similar answer was given on the last post of the thread here: https://www.scrum.org/Forums/aft/243
I would recommend taking the practice test to check what those questions are like, they should be very representative of what you can expect on the actual test.