Hi Asya,
One of the most important things to remember when you are buying a mattress is that a mattress needs both relieve pressure and keep you in alignment and to do that it needs to be both plush and firm … never one or the other.
Without good pressure relief … you can end up with poor circulation, pressure points, tingling, joint pain, and numbness.
Without good alignment … you can end up with back pain.
So the first key is always to know how soft a mattress needs to be on top and how thick this soft layer needs to be (depending on your weight, shape, sensitivity to pressure, and sleeping positions) because these are what mostly relieve pressure.
The second key is to know how firm the lower layers need to be because they are mostly what keeps you in alignment.
This is why mattress ratings can be so misleading because they don’t tell you which part of the mattress is firm or how firm and which part is soft or how soft.
Here are the steps I would take in the mattress shopping journey.
Step one is to do a little bit of reading. Just enough to help you ask better questions and have a sense of the different materials and the different types of construction and how it relates to different people and sleeping positions. To do this … I would read the overviews in the mattresses section of the site. When you’ve read these you will have a clear sense of which salespeople know their product and how to fit a mattress to your needs and preferences and which are only there to make some money … know little about mattresses … and are more interested in their commissions and the store’s profit margin than they are in your long term satisfaction.
Step 2 is to avoid as many as possible of the worst choices and the traps and pitfalls of mattress shopping. This means eliminating the choices that will confuse and frustrate you and do little to help you find your perfect mattress. The guidelines here will help with this. In essence … stay away from most mass market outlets ad major brands or any outlet that won’t tell you layer by layer what is in their mattress.
The next step is to identify the better stores within reasonable driving distance and spend the majority of your time there. These will either be factory direct manufacturers that make their own mattresses or smaller sleep shops that sell smaller, more local, or higher value “alternative” brands and are transparent about the materials inside them. What the chain stores will call “off brands” in the hopes you will believe they are lower quality. While a drive may take some time … it will also save you many hours of frustration in trying to make meaningful comparisons between mattresses that are impossible to make without knowing the materials in a mattress and without a salesperson that has the skills and knowledge to focus on why each mattress may or may not be suitable for you instead of just telling you the marketing stories that are more designed to get you to buy than to educate you about the mattress.
In your case the closest factory direct manufacturer is in Syracuse.
NOTE: This is an “oops” and the list is centered around Bridgewater, NY instead of Bridgewater, NJ. I’ll leave it here for those who may be searching for the better options near Bridgewater or Syracuse, NY (Note: I’ve also included the better options or possibilities I’m aware of in and around Ithaca and Binghamton as well). See reply #4 in this same thread for some “closer” options to Bridgewater, NJ.
http://sleepmastermattress.net/ Local factory direct manufacturer in Syracuse and Cicero, NY. They manufacture their own line as well as WJ Southard and Bemco mattresses. They make a wide range of all types of mattresses in a wide range of budgets from innersprings to memory foam to latex and use better materials and have better value than the larger manufacturers that are so common in the mainstream industry. Post #9 here will give you an idea of the type of experience you can expect there. I think highly of them and there are some good quality choices available here.
If for any reason this is too far to drive (although the drive will probably save you a great deal of time and frustration overall) … then there are a few local stores (within 20 miles) where your odds of finding something that has higher quality and value may be better but this will take more research and knowledge on your part to find them.
This means that you would need to phone the retailers that you are considering visiting and “interview” them before you walk in their front door. One of the key qualities of a better outlet is the willingness to give you good information on the phone and help you “pre-select” a few mattresses that would be worth testing. Questions like “do you give your customers a list of all the layers in your mattress including the density of any polyfoam or memory foam that is in it?”. “Do you have any latex mattresses that don’t have more than an inch or so of polyfoam above the latex?”. “Can you tell me the layering of any memory foam mattresses you carry that you think may be worth testing?”. How much is … “this” … mattress in queen size mattress only?". Outlets that can and will answer these types of more specific questions cheerfully and without “resistance” and are clearly interested in helping you rather than telling you to “come in and lay on the mattress” before they give you any information are the ones worth visiting. You will get a clear sense of what to expect by asking these types of questions and it will save you watching a lot of eyes roll and “I’m going on a break” comments if you go into the store and start asking questions about materials and construction without an “interview”.
There are a few other retailers that I’m aware of in the larger general area (Syracuse, Bridgewater, Binghamton, Ithaca). I’ve indicated the brands they carry that I would focus on that you have a better chance of finding out what is inside them and that may have some better value (depending on what is in any model you are looking at and the price of course).
http://www.syracusemattress.com/ Syracuse, NY. They carry Therapedic, Eclipse, and Symbol mattresses as well as Savvy Rest latex component mattresses.
https://contemporaryfurnitureny.com/category/bedroom/mattresses/ Syracuse, NY. They carry Pure Talalay Bliss (Pamper, Nature, and Balance) and Magniflex.
http://adirondackhomefurniture.com/mattresses/ Syracuse, NY. Restonic including latex and memory foam
Imex Furniture New York Mills, NY. Restonic
http://www.sleepischeap.com/ Retailer in Watertown, Fort Drum, Pulaski, Oneida, NY. They carry Eclipse, Therapedic, Hemingway, Eastman House, American Bedding. Can order custom sizes.
http://www.metromattress.com/ Many stores throughout the area. Pure Talalay Bliss. Make SURE they are willing to identify all the layers in their mattresses. Chain stores like this typically tend to focus on sales techniques rather than quality information. NO MATTER WHAT … never buy anything at a chain store on your first visit. ALWAYS leave the store and leave decisions till at least the next day no matter what “deal” you are offered. Large chains like these can be “dangerous” to the unwary consumer 
http://www.olums.com/ Johnson City, Vestal, Syracuse, NY. Natura. These are high quality talalay latex mattresses.
Home Green Home | Ithaca, NY | Green Living Goods Ithaca, NY. Carries WJ Southard, Savvy Rest. High quality but more “premium” mattresses.
http://www.americasattic.com/index.html Johnson city. They carry Gold Bond. Make sure you can get all the specs of any mattress you consider here.
http://sturzenfurniture.com/bedding.php Sayre, Towanda, PA. Sierra Sleep, Therapedic.
http://www.hlstephens.com/mattress.aspx Montour Falls, Horseheads, NY. Sayre, PA. Restonic
This should help you go from where you are to finding the best possible mattress within your budget and that will suit both your needs and preferences.
Take your time … and never worry about missing a “sale”. Most of them are fake anyway and high quality mattresses are available every day of the year at better prices at the better manufacturers and retailers. If you have questions along the way … don’t hesitate to post them here.
Phoenix