I've seen far more worse and better anime OVAs in the 26 years that I've watched anime. Dragon century is for me quite in the middle and since this was like other OVAs a one-shot title it was '' bearable" but as well it seemed a bit unclear if you don't watch it several times to get it. First of all part 1: 1990 AD, I was surprised by the violent content and would have LOVED IT if I was like 12 years old or something :).
Clearly there you can see how the human dominion comes to a crash course once dragons appear with very bloody consequences (don't be a bitch by the amount of blood if you can't stomach it) and a girl gets involved by saving a dragon egg that hatched.
But as the story progresses there is a meaning to the dragons appearance when a demon god fucks up the human world and needs to be stopped and in some way the girl and dragon do it, leaving some destroyed buildings around, and a timerift opens so dragons can enter the human world.
Part 2 on the other hand, you will be confused the 1st time because it starts in a new era named R.C 272 ( Ryuu Seiki translated to Dragon Century) .
It appears that the human world is changed in to a human/dragonworld where
dragons that lives far longer than humans are used as pets, fighting in arenas for fame.
The young hatched dragon from part 1 is now a few hundreds of years old and encounters a young girl that possibly is a grandchild in the future related to the girl in part 1, and for some reason the demon has be revived or whatsoever which is time for the dragons to stop and save their world, and it felt unfinished.
The animation was 'respectable for its time', it was cheap but not THAT cheap, but hey what do you expect from one-shot 2 part ova.
The characters themselves were quite good, I had hoped that a bit more attention was given to the dragons since they are the main part of the story, but I had no problems with the female character, she had an undaunted, non airheaded, strong believing and understandable personality that drops heavily in part 2. Part 2 had more dragon characters and human characters but was all about it.
It was enjoyable on the basis that it's just a short popcorn OVA and was good to me but could have brought soo much more potential on the goddamn table, but after so long it is forgiven. So yeah in the end its up to you to make a opinion.