My most recent time sleeping airside in Pearson was in Feb. Now carry a small inflatable air mattress in my carryon as YYZ's floors are cold and hard. Only problem was the loud snorer a few chairs away.

By the way, on the same one week weather impacted 9 segment itinerary, tried to stay overnight airside after a cancellation in Montreal, but was awakened at 3:30 am and forced to go landside for 30 min as the airport apparently had closed at 11.00 pm and didn"t reopen until 4:00 am.