First off, this anime is quite old, and I supose people will kinda only really like this, if they are hardcore anime fans and can apprecaite its old, or people who saw it when it first came out. The story is about 4 brothers who each have a hidden power to turn into a dragon, each dragon has 1 element, such as fire, or wind. The brothers at the start of the anime don't know they have this power. The story is basically about an organzation that knows of the brothers powers and trys to capture them, thus leading to the brothers knowledge that there aredragon kings.
It sounds quite basic, but there is a nice plot twist in there.

The characters aren't that special to be honest, although I'd say most people will be able to pick a favorite out of the brother character, and there isn't really much devolpement between the brothers but there is regarding their dragon powers.

The art isn't going to blow you away, since it's an old show, but for it's time it wasn't bad at all. The sound from what I can remember does it's job, but compared to new anime it wont be spot on.

However with all that being said, there is a certain enjoyment in this anime, and I'm not sure what it is, I think the creator must have had great passion for his work, and you will find it a joy to watch, I know i did. however I wouldn't recomend a rewatch if you saw it when it first came out, and this is the anime that hooked you into anime, as it hasn't aged that well.

Overall, Give it a watch if you're a huge anime fan and must see everything, It won't blow you away, but I don't think you find it that bad, and you'll find some enjoyment in here.