I ordered the medium for my son who wears size 7 and it fits him perfectly. He's on the skinny side, so if you're ordering for a size 8, I'd go bigger. The outfit seems to be good quality, the details on the fringe and trim is nice and not flimsy. The material is a bit thin- I could see the Angry Bird on the butt of his underwear through the butt of the pants. Nothing a pair of shorts under it didn't fix.  He liked it, was comfortable in it and got lots of compliments in it. The pants are full true pants with an elastic waist and the shirt isn't one of those awkward costume shirts that's made like a fifth grade home-ec project- this one has shape and fits like a real shirt. It really is simple and soft and comfy but looks much more intricate.

What keeps me from giving 5 stars is that it's not what is pictured. The picture shows the shirt as having blue trim, multiple layers, etc. Ours came with a shirt with just one "bib" type thing with red trim. I don't mind because I actually like it better for its simplicity. But on principle, believing you should get what you are promised, I'm only giving it four stars. Still something I would recommend and buy again.