Hi JayD2014,
You can see the guidelines I would suggest using in post #4 here.
The mattress is a pocket coil yes (individually encased coils) but if you look at the top 5" of the mattress you will see that 4" are very low quality materials (less than 1.8 lb polyfoam or 4 lb memory foam) and the last inch is “borderline” so it would definitely have some significant weak links (more than “about an inch or so” of low quality/density materials) and I would avoid it. This would be a very risky purchase.
Phoenix