If you hate Starbucks, don't expect to love it.
The rest of this review is for intelligent people: go at wintertime. November is best: they still have the pumpkin spice latte AND the peppermint mocha.
Skinny peppermint mocha. So you can fool yourself into thinking you're drinking some kind of miraculously delicious-tasting form of Slimfast.
They're quick, and delicious. The location is cute (on the street corner in the old city) and convenient (across the street from the Palais des Congres)-- so if you get sick of waiting in line at Tim Horton's (where they do have better pastries-- but no peppermint mochas!), this is a great place to be. And if you're in town for, say, a conference... As the days go by, you'll see more and more people carrying around Starbuck's beverage cups.
Not bashing Tim Horton's, but there definitely seems to be a trend as people become more and more in the know about the restaurants and cafes within kissing distance of the convention center...