My son informs me that he has to provide his own bed next fall when he moves into his [strike]off-campus tenement[/strike] fraternity. He has been using a Tempurpedic XL topper handed down from his big brother on his dorm bed and that seems to work fine. Best solution? Low end inner spring? (And this is from a Brooklyn Bedding Aloe Alexis owner.)
There really isn’t a single “best” solution because it will depend on your budget and on which type of mattress would be the best “match” for your son in terms of PPP (Posture and alignment, Pressure relief, and Personal preferences) and on whether you plan to use the same topper on a different mattress or buy a new mattress completely without the topper. Different people can have a very different definition of “best”.
Your son may also have his own preferences for the type of mattress that he likes best (innerspring, memory foam, latex hybrid, polyfoam etc) or he may only know that he likes the current mattress/topper combination he has been using which would be “pointing towards” a sleeping system with a top layer of memory foam.
If you plan to use the same topper then a firm mattress of any type in a lower budget range that doesn’t have too much in the way of lower quality materials or an obvious “weak link” will probably be fine although you won’t need the highest quality and most durable materials for a mattress that is only being used for a few years.
If you plan to purchase a mattress without the topper then if he likes memory foam it may be worth considering a relatively low budget memory foam mattress.
Since you have already dealt with them Brooklyn Bedding it may be worth considering their sister company Dreamfoam who would certainly have several mattresses that would be suitable in terms of budget and the number of options they have available and would be well worth talking to on the phone once you have decided on your budget range. There are also some other options in the online lists that are linked in the tutorial post that could be well worth considering as well. Some of the better online options I’m aware of in lower budget ranges are also listed in post #4 here.
If you would prefer to purchase locally or have him try a mattress in person before buying it then if you let me know your city or zip code I’d be happy to let you know about any of the better options or possibilities I’m aware of that are close to you.