When I adopted her, they were like, "she's big. You'll need a large carrier." I had purchased this "extra large" cat carrier. I had checked the reviews and people were saying it was great for Maine coons and what not. I went to go get her, happy with my research, and they just looked at it and said "Um... That's not gonna work."
We ended up trading carriers. She still uses it, though now she has a ton of room in there.