Forget about the Dragonball manga and forget about the Dragonball/Z anime - view this as a stand alone story... Following the above steps only makes this special worst! The reason why? The story has little substance - a higly basic and short plot dependent entirely on the well known franchise. Now, I'll delve further... Story... Goku's dad, Bardock, in his last special, faced off against Friezer. Within this special, instead of dying within the blast theat blew up his planet, he was somehow teleported into a past time period.Bardock develops a soft side for a cutsie young, kind alien who just wants to help him.
Not too long later,he comes across a new antogonist, an ancestor(?) of Freizer.
Bardock becomes a super saiyan (quickly and stress free).

Art...
Good art - can't fault it.
DB/Z artwork back in the past was good - especially concidering it's age - this is pretty much the same.

Character...
Mary Sue galore - Bardock comes across as a fanfiction writers highly zealous creation - not too 'hardened' and prone to power-up's that aren't consistant to the original story.
We have the cute, highly friendly aliens who only scum of the universe would hurt.
We have a goofy villian who, in a 20 minute special, couldn't possibly be more then laughable.
If these characters were applied to a new anime - it would automatically get labled 'generic' ad I doubt a manga pilot would go any further?

Enjoyment...
Very, very little!
Aproaching this from a neutral perspective - seeing this as nothing more then a loose adapation and forgeting that I had skimmed threw the manga of this (I can filter stuff out of my head, which I'll do after this review).
Seeing the positive - DBZ attention is a good thing?
The above atitudes fail to brighten up a highly dull, unlikely (if you follow the series) fanwork that makes you question what extent the author of this actually followed/enjoyed this series?

Overall...
It's a fail - the most attractive thing about this is it's length.
It's nothing more then fanfiction - and there's better fanfiction out there, trust me!