Hi lalunia,
Just in case you haven’t read it already … the first place I would start is post #1 here. This will arm you with the basic information you will need when you are mattress shopping.
Some of the better possibilities I’m aware of in the Baltimore area are included in post #2 here.
Always make sure that no matter where you are shopping or what mattress you are considering that you are given the details of every layer in the mattress including the more specific information about the quality of all the materials that is usually missing from many spec sheets. The better salespeople will also be able to explain to you what they mean and how to compare them and tell you which types of materials are more durable but if you need help “translating” any of this feel free to post the details on the forum as well 
Without this more specific information there is no way to know the quality or durability of what you are buying or be able to make meaningful “value” comparisons between mattresses.
Phoenix