Mickey was one of the ones that was weird on our trip. The wait time posted was 40 mins, but visually looking at the line there were only a handful of people standing in the velvet ropes section that you see when you walk in. The CM standing in the middle at that point (b/w the Mickey ad Tink lines) specifically said the wait was more like 10-15 mins. With the reports I've heard of posted wait times being inflated, combined with what the cm told me, was like "oh, great! It'll be shorter than that.". It wasn't. It was the full 40 min wait just to get into the M&G room (before actually meeting Mickey) While there were only a few people in front of me standby, the SB line stood still for long periods of time while FP+ holders entered (there weren't many FP people in line when I entered either, which is why I thought it really was a short line. Many FP+ entered the line soon after I did).
In contrast, I went in SB to see Tink right after Mickey, and it only took 10-15 mins to get in to her actual M&G room.
If at all possible, I would probably try to see Mickey during EMH (maybe on your way out of the park) when FP+ won't be a factor in the line.