If you buy yourself the right mattress, it will guarantee that you get a great nights sleep every night, and that you enjoy the maximum amount of comfort while you are asleep. You can even achieve this by buying a cheap mattress if you know what you are looking for, and if you are prepared to spend a little time to find the perfect mattress for you.
The type of mattress you end up buying will very much depend on your personal preferences, do you prefer a softer mattress or a harder one? The key to knowing which type will suit you best, is to make sure you visit a few different mattress stores before you decide to buy and try out all the different firmnesses of mattress that they stock.