Okay. I will now say what I think of the different 'Astro's.
To be extremely honest with you (I know a lot of people will disagree with this), but I dislike Astro as he appeared in Pluto, especially the fact that they removed most of the things that made Astro 'Astro', such as his signature red boots, his horns or even his "wittle tushie". Uran has the same problem; come to think of it,
most of the characters have that problem. I don't mind a bit of character changing, it makes the plot more interesting, but when you've changed the main character LIKE THAT, whats the point!?

Again, there will be some disagreements here, but personally I believe that the '03 Astro is the best drawn, in fact, so is most of the characters. I liked how they maked the characters 'clean', if you know where I'm getting at, but also I just like how the characters are drawn.
Tenma and O'Shay wouldn't be too happy if they saw how they looked like in the film. I wasn't too happy either. But the point is Imagi didn't have a lot of choice, that is just one of the many issues from converting anime/manga to C.G.I (2D to 3D), and imagine for a bit that Tenma looked exactly like he looked in the manga/anime. It'll look strange
.