First, great topic!
Well, I have steered clear from playsets for the most part because I have no good way to display them. Don't chastise me for saying the following.
I have an office / collection room that is 10 feet by 12 feet. I just cannot get myself to fully make it a Star Wars Room. It's just personal preference to make the room overwhelming with Star Wars stuff thus I never went after playsets.
Now that I am finished with my "100" I may start, who knows I could have a change of heart.
I agree with Chris M the Death Star Playset is the one playset with the most sentimental memories associated to me. Every year we persuaded my dad to let us open one package on Christmas Eve. One year I went for the biggest present, low and behold it was the Death Start Playset
! I remember opening it at about 11:00 PM and completing it and playing with it until about 12:30 AM. I feel asleep on the floor next to my playset, fond memories.