Ask HN: Should vs. expect. What do you like?

There are two popular assertion pattern for testing the Javascript. Should and Expect. What do you like more? And what is the reason? I just want to know.

My personal flavor is should, but I usually use expect for codes that has to be shared. Because the expect has more reference and documents. (For example, even api docs of chai use expect default. http://chaijs.com/api/bdd/) It reduces explanation costs when you use should.

How about your case?