I watched this when I was 12-14 years old, after I have already damaged my brain with Pokemon and Yu-gi-oh. I did enjoy it, but even 12-14 years old kid can see why is something happening (for the coolness and for money) and major...failures.
Story:
Take Yu-gi-oh, make the deck with one card, that is getting stronger (Pokemon?) and make a basic toy. Add something techy and here you go - you have a Beyblade! No, the story isn't that bad, but that is just because it is MADE for being bad. Who cares actually? The bad are bad, the good are good, one good guy is becoming bad (Sasukeeeeee!) and then good again. Friendship, love and peace always prevail.
Art:
Since it is MADE to be like an average Yu-gi-oh+Pokemon shonen it has to have something to catch the eye. The battles have effects, the Beyblades have very good animations, the creatures are very good too. So far 9. But the overall animation is not that good, static backgrounds are common issue and are very different from the battles. If you have watched Code Geass you know that the animation can be much better in that direction. But are there 12-14 years old kids have seen it?
Sound:
The fact that I can't remember anything bad about the sound (except "Let it rip" or common curses and screams) is the reason for the 6. I remember the good voice acting, good sounds when they have "Let it rip" and the screams of the monsters.
Characters:
Very shonen, very immature and pretty well developed. Another strong point. When you think Naruto is an idiot and Sasuke is an EMO, then you see, that the characters are not so standard (well, they are, but in a better way). They pretty much behave like humans and not like the average shonen idiots (Goku, Lufy, Naruto, etc.).
Enjoyment:
You know when a thing is something more than the sum of it's parts. Well, here it is less. I liked it, but I didn't really enjoy it nearly as much as other shonen titles. Again - Yu-gi-oh and Pokemon are much more fun, because they make a new world - the author makes the rules or breaks them. Here they are trying to make you believe that the world is real. But it is not. And even a 12-14 years old kid understood that.
Overall:
The overall score is a little higher, because it is unfair such a good, pure shonen anime to be hated that much. It is unreal, but who cares?! Hellsing: The ultimate isn't. Berserk isn't. But they are good, aren't they? So if you like animes for kids - go ahead. I like a little more realistic and mature titles.
With a friend we made an army to take over the world - Pokemon hooligans, Bayblade Pedobears and cards-cerebral-destroyers. Well, they can destroy mountains (Pokemons), crush walls and are like power plant s (Bayblades) and can cause serious, sometimes deadly brain damage (Yu-gi-oh cards).