The anime's story is a sad one at the most. It has been looked down upon because of the toy franchise it was originally based off of was not exactly the coolest thing to buy and the fact that is was on Cartoon Network were a lot of other "kiddie" animes have been shown. But the matter at hand is it is actually a very good anime. I know a lot of it can be pretty cheesy, but the actual story itself is actually a good one. I for one ALWAYS hated this anime, but when my friend I got this game called "ZOIDS: Battle Legends" and forced me against my will to play it, it drove me to watch the show. After watching ZOIDS: New Century Zero, I was already hooked on the show. I would actually like to see this anime brought back to television, because it is a really good series and about number 5 in my list of top animes I would defiantly recommend this to anyone who loves the ideas of piloting there very own animal based giant robot.
I agree, if you can find this anime or stream it on the internet, you should because it does have a good story and is funny to watch, if not for it being made to promote a toy, it could have done well on its own, this was shown on toonami back when CN actually was about the cartoons rather than being a joke that it is today, however this show was dubbed by Ocean so the voice acting is not terrible, but the animation that was not CG does show it's age, other than that go watch it.