Zero Tester

Take this piece as my relatively amateur and beginner level of review.

Zero Tester is an retro mecha anime series that were aired in the 1970s. While it may be nostalgic for some viewers mainly for featuring Jet Fighter vs Kaiju,a rarity compared to it other wider known counterparts from its time like Mazinger,Getter, it falls short in several areas from a viewer's perspective.

One of the anime's weaknesses lies in it kaiju of the week formula,while it was something acceptable during it times,it keep repeating same problem regarding the trio over and over again while simultaneously giving surface level of character development for the trio in ... each episodes,mainly for Hiroshi and Shin quarrel,only for in the next episode you will see the growth the cast in previous episode will get nulled as if it never happened in next episode for the unnecessary drama and tension,like they never learned from their mistakes in previous episodes and it will keep repeating the same thing until last few episode where they somewhat finally matured enough for their task.

While the animation is understandably dated,it might difficult for some viewer to engage with the characters' dialogue and emotions due to dramatic expression and the reused fight scene frame.
This probably can take away from the overall viewing experience, and it may be jarring for viewers accustomed to more recent anime style.

While the anime's action sequences are often exaggerated and extravagant, its plot is too simplistic to sustain a viewer's attention. The dialogue is often predictable,and there is very little worldbuilding as well and the characters lack significant arcs or development and importance.

In conclusion,Zero Tester is a nostalgic unpopular and relatively unknown to wider audiences piece in anime history,but falls short in its several areas.Fans of classic anime may enjoy the show for its nostalgia factor like the music especially the catchy opening song,Jet combination/gattai,but it is unlikely to appeal to newer audiences or other with high expectations,only recommendable to people who really liked mecha genre and wanted a slice of it historical value,otherwise steer clear if you expecting something memorable and good storytelling on this anime.