I don't know if they will continue to use their uniforms as much. I read somewhere that they are trying to get the students to wear more muggle-type clothes, to show that the kids are growing up. So we'll see...

I like the uniforms hope they use the more.

I like how they have different ties for different houses.
I know several people irl who have gryffindor ties that look similar to the movie ones

I think those school uniforms are great and they looks nice too and I really like them a lot and I agree robes are Wizards normal clothes but I like those school uniforms a lot indeed. Especially I like those Gryffindor's uniforms.

I liked the old uniforms better because they were like what I pictured them to be and now in PoA there more fashionable and they wear muggle clothes way too often. It just doesn't seem like a magical school, just like a normal one.

Why would they change the uniform? It's always been the same. Green and silver tie for slytherins, red and gold tie for gryffindor, yellow and black for tie for hufflepuff and blue and bronze tie for ravenclaw. Other than that, the uniforms are all the same.

I have not seen much of a difference in uniform from movie to movie, just the way they are worn which is normal since the characters are growing up and all. The muggle garb was never worn for a classroom scene. I see nothing wrong with seeing the characters in normal garb after the school day is done.

I love the uniforms, I think they look really cool. The muggle clothes are just.....boring. Bleh. Ick.

Both could be right.

Now i'm not entirely sure, but judging from the descriptions in the books, it doesn't sound like they had uniforms under their robes, it sounds more like they wear their, as you guys put it, muggle-clothes. It hardly ever describes anything like this, but in the films they wear dress shoes, wheras in the books, it mentions Harry's "Sneakers"(GoF, page 173 US PBE, Triwizard Tournament Chapter) And a few other things suggest they just have normal clothes under them. I am also unsure what their robes are like, in the films and Mary Grandpre's illustrations, the robes are like jacket robes, but in the UK illustrations, they are like a full body kind of robe, and it might just be that way in the books, not entirely sure, though, i'm not JK, so i can't speak for something that isn't made clear to us. But in the books it mentions they wear robes quite a bit, even more than in the first two films bar a few moments where there is a mention of pajamas, but the first two were more accurate here, but in the book, it is possible they might be in muggle clothes under them. Harry in a pair of jeans, Hermione, jeans or a skirt, who knows.

I like all the Hogwarts uniform I want to have one

I think the difference is small.