I usually fly Delta from the US to or through Pearson, and its an okay airport. If you do customs in the Delta terminal its a four star airport. Customs through the Air Canada terminal? Two stars. I had an A gate the last time that I seriously was trying to figure out as I walked there how a airport gate could be in a basement. It was like airport purgatory. Even the staff working nearby seemed to be on some sort of probation or punishment stint having been banished to this remove and desolate location. There are tons of food options, the transportation between the terminals is efficient...it has its good, and bad...its pretty average.