Platform beds are ok for comfort, about as good as a matt & box combo - but not a replacement for Matt & Boxsprings. The matts will break down quicker and not last as long on a platform as a combo (matt & Box). That's what was found, when working in my past job for 24 yrs. Bedding is the biggest racket in the furniture industry. If you go that route, be sure to rotate your matt - flipping head and foot and get a flippable so you can use the back and front (flipping) also. You really get what you pay for with bedding. More money, should equal better quality / longevity of product - but, BUT . . there are unscrupulous manufactures and dealers out there that try to pass of lower quality as higher quality / priced product. Be sure to have the saleperson or bedding supervisor explain the differences in materials used, construction techniques and mfr's. If a guy finds a very good quality matt with good quality springs - it can work in a platform and last - but it cost. So, are you better off buying less expensive bedding and planning on junking out and replace in a few yrs or putting twice or three times the money in one and hoping it last as long as two or three less expensive sets? ? ? ?  Seems some of the better values in bedding are from the independant shops that sprung up in the larger towns / cites and are not the name branded bedding seen across america.

Edit: I should add, bedding mfr's used to offer a platform matt - I dought the major's do today as they really want to selling bedding and to sell bedding it has to wear out quickly. On average a good quality bed should be dumped and replaced about every 10 yrs. coincidentally, that's about how often your body changes and could require different support . . . .