Hi tltb1,
The only way to give any meaningful opinions about the quality or value of a mattress or to identify any weak links is by knowing the specifics of all the layers and components in the mattress. Without this you would be making a completely blind purchase without aving any way to make an informed decision.
Of course if you can provide the details of all the layers (which the retailer should provide you) I’d be happy to share my thoughts about it but in most cases you won’t be able to find this out with the major brands which is why the guidelines suggest avoiding them completely in most cases.
The Phoenix list is in post #4 here but as you know from the membership list three of them are members here which means you are fortunate to have some local choices available to you that have exceptional quality/value 
Phoenix