We ordered the 5' 24 by 24.  It works for time being.  We do feel that it will go flat within 6 months.  They replaced 2 of our chair cushions on our Lanai.  Both my husband and I are overweight and I am sure that has a lot to do with it.  We feel that if It was 8 inches thick would have been better for us.  Over all we are pleased with them.