I went to the Premium Plaza lounge at YYZ - terminal 1. I've been to a number of lounges throughout Asia and North America and I must say this is one of my favourite in North America!
The sitting area was not super big but it was clean and the support staff was super polite and helpful! I arrived on a wednesday afternoon and it was not super busy like all the Star Alliances lounges usually are.
What I was most impressed with was the assortment of food and drinks! There was seafood pasta, BBQ park (char sui), salad bar, cup noodles, salad bar, cereal and an assortment of dessert. The food wasn't premium quality but I was hungry and had lots of pasta and soup! I'd definitely come back!