Just got out. I'll definitely do a more detailed write up later, but these are my initial impressions:
-UWorld and First Aid covered >99% of the exam. There were literally only 2 question where I had absolutely no idea, but even those were arguably fair game material and I simply failed to connect the dots / recognize the underlying principle. That said, I totally see now why a lot of students think that there are "wtf questions" or experimental questions on Step. That's because about ~5% of the questions are pure logic puzzles where you have to apply UW/FA knowledge to arrive at the answer by process of elimination. For example, several times the correct answer was a drug, disease, or biochemical entity that is NOT covered in UW/FA, however you can totally nail the question if you can recognize why all the other answer choices are wrong. This category also included some questions that I would categorize as "trick" questions, where you totally recognize the disease, but there is some bit of information in the stem that totally disrupts your usual heuristic or perhaps the answer you're expecting isn't included as an option. In my opinion, one of two things could be going on in this type of question - You may have failed to study some esoteric nuance of the topic, and they want you to step out of your comfort zone and pick the "obvious answer" anyway even if it doesn't feel totally right. The other type is the antithesis of the previous form -- where they describe what seems like a classic pathology EXCEPT for some bit that doesn't fit, and this time you're not supposed to ignore it because the answer is actually a related but slightly different pathology that you've never heard of but which you can discern based on its name.
So overall, with the exception of those 2 questions that seemed completely foreign, the test seemed entirely devoid of "experimental" or "wtf" questions. If you told me that every single question counted, I would believe it.
And then about 5-10% of the exam consisted of questions that were simply very difficult but "fair game." These were mostly physiology or biochem questions where I had to do mental gymnastics to build an argument for a particular answer, and even then I wasn't totally confident in my answer. These are the type of questions where I knew I could figure it out if I had extra time but couldn't process it in time to arrive at a conclusive answer. Sometimes I had to resort to playing "which one is not like the others" with the answer choices, lol.
Finally, there were a handful of questions that weren't particularly hard and would otherwise be a slam-dunk, but I just couldn't remember something about the topic and spent way too long thinking about it. Luckily, there were only like 2-3 of these, and I think I got them right in the end. This is where memorization pays off.
Ethics, stats, imaging, and auscultation were EZ-PZ.
Stems weren't any longer.
The "Step 2" style question rumor is a complete myth. The clinical management questions were pure logic questions. Would knowing the management algorithm for X disease cold by having read UptoDate make it easier? Duh. But that's not the exam writer's intention. The questions were 100% written for pre-clinical students and can be answered with common sense if you have solid fundamentals.
A couple histology questions were tough.
Time management was only slightly tougher than practice tests. I still finished the blocks with ~20 minutes to spare, but the difference was that I marked way more questions. I mark very liberally to begin with, and today my threshold was even lower because of the high stakes. This may have been a strategic error in hindsight as I had too many marked cards to review on a few blocks. However, I settled into a strategy of "hand-marking" the ones I REALLY wanted to come back to by writing their # on my dry-erase sheet.
And finally, I totally reject what has become somewhat of a cliche expression among med students that Step 1 feels like "7 hard blocks of UW." To me, it felt like 7 blocks of really hard NBME. I think most people just say its similar to UW because the software looks just like UW. However, the "feel" of the questions, in my opinion, was pure NBME.