What about surface area? Was it five gallons of oil in a 5-6 gallon container?
I'm not crapping on what you found outright, I'm just pointing out where there could be differences.
My Better Bottles smell clean and they are 5+ years old. I used buckets for years, and yes, they did hold a bit of an aroma. This is partly why I'm hesitant to upgrade to Speidel fermenters.
Doesn't Leos ferment in modified conical storage tanks?