Multi or Scatter instrument for random ambience sounds?

Hello!

I’m trying to set up an instrument that will play random sounds at random times with quite a big gap between them, like several minutes. I dont want the sound randomized in space and maybe not even in volume. Just randomized in time. How do I do this best, with multi instrument or scattter? And also, should I put it in the same event as, say, background noise ambience?

Would it be enough to set chance in trigger behaviour pretty low, like 20%?