That's an interesting discussion.
It's somewhat possible to have a strong opinion based on the spoilers if the information itself is powerful, like if next week we learn that "Luffy becomes SSJ and goes flying to Saturn, giving up being Pirate King after falling in love for Alvida". Geez, that's quite a spoiler, I don't know how I feel after such a sudden turn of events.
That said, I'm of the opinion that the writing/drawing itself is extremely more important than the information it holds, because that's where we find the strenght of any art form. That's the difference between good and bad writing, although the evaluation will be subjective. Obviously, the content matters too, and the information itself can be very powerful, but that's something much better grasped when you contextualize it with past and future chapters… and you can change your mind about the information when you actually read it (since the experience, the emotions and the subtleties will hit you).
It's very often that we see people changing their minds after reading the chapter, so that's some evidence of what I'm saying. Of course, you can't avoid creating expectations when you read the spoilers, but many people do take spoilers into their hearts much more than they should.