Hmmm. Seems odd and opposite to a comparison of the thickness of the glass would make it less gallons to my thoughts. And heavy. An email would clear it up. Could be a typo.
So from some previous negative experiences I have had with things, look up "problems" with x name company in a search not just reviews. For any purchases like that. A check of problems or other words which could be consumers not happy might use. No one has real 100% satisfaction when it involves big tanks and shipping and some people who complain are just crazy but sometimes it can alert you to important issues.
The reviews are often skewed. My daughter bought a car and the guy wanted her to leave a 5 star review before it was even all said and done, and she didn't because of his behavior. He actually cornered her, literally and confronted her about her review as she was leaving, telling her she needed to change it. So reviews can be bartered and pressured for. And bad ones can often be deleted.
New to FW fish? First tank in a long time or EVER??? Need some info on keeping fish?
Start here - Aquarium Advice Article
FW Favorites right now Clown Loaches, any shrimp - SW Vase Red Mangroves