I can't give this series any less than a 10, just because of the dope memories and the fact that DBZ was the first series of it's kind.
Coming home every day to watch the new DBZ episode on Toonami after school >
Vegeta killing Dodoria, Zarbon, and the rest of Frieza's goons >
Krillin and Gohan making Metal Gear Solid moves on Namek >
Goku going Super Saiyan for the first time >>>>
Trunks murking Frieza >
Piccolo fighting 17 >
Tien pushing Cell back with the tri-beam >
Gohan beating Cell >>>
The nostalgia
I will say this however... DBZ has it's flaws looking back.
I never liked how the whole series became the Goku and Vegeta show while Piccolo, Krillin, Gohan, and the rest of the OG crew fell by the wayside.
And to be honest, I think One Piece, Fullmetal Alchemist, Jojo's Bizarre Adventure, and Hunter x Hunter have since surpassed DBZ for the most part. (Yu Yu Hakusho is also lowkey better IMO)
But still, it's DBZ.
DBZ!
It's the series that laid the groundwork for pretty much every action/shonen series worth anything.