Anyone have any ideas of a good mattress brand that has extra firm and will last for at least a decade or hopefully two?

So

We’re replacing our futon with a twin mattress for me postpartum after baby #2 comes. Dad will sleep with baby #1 in our bed and i will sleep on new mattress with baby#2 in bassinet.

Now we’re also hoping to use this twin mattress for baby#1 when he gets older.

I like super firm. Our bed right now is an extra firm that cost like $1200.

The same brand in a twin is about 900$. We do nottttt want to spend that much for a mattress.

Anyone have any ideas of a good mattress brand that has extra firm and will last for at least a decade or hopefully two? Annnd not too expensive? Preferably under 500.

Thx!