Same as MBS (Paradise Honey - lots of hits on Google), then. When I asked I was told a minimum of 100kg per metre cubed.
I know some out there were working on a lot less earlier in the year. One supplier started at 'about' 60 and were increased to a 'machine setting' of 80kg/metre cubed. I still did not think that was likely more than 'just adequate' as I did hear reports of chewed items at the lower figure, so declined to do buy any from that supplier.
Durability, (you jumping up and down on them, per eg!) might be compromised at those lower densities, even if chewing by the bees was prevented. So, yes, quality counts.
Many think of packaging when poly is mentioned. Proper hive poly is just as tough as wood, I have abused it over the years in many ways including dropping at hive at 40mph! Colony, hive and queen all survived though I could always tell which roof it was as it was a little chamfered on a corner and I stress the little.