Hi nosugartonight,
I’ve also talked with Val at Mattresses 24/7 and we had a great conversation and I think highly of her.
As you mentioned she is no longer supplying factory seconds or returns (unless of course she were to specify that it’s from a mattress that was returned to her).
They would make a good choice for someone that was looking for more basic options and didn’t need some of the options in design or materials available with other suppliers, that didn’t mind that there may be a very slight side to side difference in ILD between the two manufacturers sometimes with split layers (if they come from different suppliers), and that was confident enough with the layering choices they make that they don’t mind the lack of any layer exchanges or mind a higher cost involved for returning the mattress.
They are certainly good value.
I also changed their description in the component layer post here because I realized that the information there was not current so thanks for bring it to my attention 
Phoenix