Pick the Mattress That is Best for You
Instead of focusing on the name brand or price, think about what you want. Do you want a soft, medium or firm mattress. Do you want a foam, hybrid or traditional mattress.
Do you sleep on your back, side, or stomach? Are you cold, hot, or a combination of both when you sleep. Do you like the mattress you have, but it is just worn out.
There does not seem to be significant scientific evidence related to mattresses that proves that one type of mattress will help you sleep better than another mattress. That being said, certain conditions (usually medical) can dictate the type of mattress you may need i.e. back problems, implants- folks with implants cannot sleep on their stomachs, etc.
Well known brands usually spend more money on advertising than less known (that is one of the reasons they are well known). Costs also may play a role in where the mattress is manufactured, warranty, and materials used.
If you can try out a mattress at your local store, and they will not honor the internet price (simply buy on line). If you cannot try it out at a local store, make sure the internet provider offers at least a 100 day trial "no questions asked" return policy, so you can try their mattress, and if you do not like it, you can return it. Most mattress manufacturers will not offer a 100 day trial period if they were not convinced you would like their mattress!
Also make sure they offer at least a 8-10 year warranty.