I just came back from Thailand, and it is a true food paradise; the food was just next level compared to everywhere else I've been.
Unfortunately, Thai restaurants in the GTA absolutely suck. Most of them are Chinese-run, and as as Thai as your neighbourhood Burger King.
Thai Pepper is run by actual Thai people, so the food is much, much better than other "Thai" (they need the air quotes) places.
Is it as good as Thailand? Not even close. But it is the closest thing in the west end of the GTA, and the people are very nice, truly deserving of your patronage.
I'd recommend the spicy basil noodles with beef; delicious.