Flew out of Pearson to go to New Jersey earlier this month. It took a long time (more than 2 hours) to get past security as there was an extremely long line and seemed to be understaffed in some areas during checkin (which caused a bottleneck effect in a couple areas). The inside was clean and had a very modern feel. There were also iPads with a variety of games to keep you entertained if you arrived early. I would recommend coming at least 3 hours before your flight if you are planning to go from Canada to USA and are not a Nexus traveller.