I would estimate that I have spent more than 20 hours, per bowl.
Although they looked clear to the average person(non aquarist)(empty),...I saw all sorts of imperfections as I unpacked the first bowl, (knowing from experience) how these seemingly small imperfections would be exaggerated/magnified 10X once filled with water.
I would estimate that more than 50% of the total surface area(inside and out combined) was "crazed"(small spider-web like, laminar cracks).
I called the company to complain about the condition, and they sent me the second one(for free), that day,..(said they didn't even want the other one back).
..you can imagine how my wheels were already turning thinking that I should learn how to buff acrylic so that I may possibly use the scratched one.
Guess what...the second one came in WORSE!! condition than the first...I HAD to learn how to buff acrylic.
That's how the second one came to be..that night I planned the new plumbing lay-out, and began my acrylic refurbishing search.
I did the insides while they were still dry, and the outsides once they were filled with freshwater,... testing the flow.