Actually, BF structure blocks have 300hp per cell while GSO blocks have 250hp per cell. Still less than HE's 400hp per cell, but tougher than GSO. They're also slightly lighter with the exception of the chassis blocks which are very much lighter.
I think of it less as an actual BF armor. I think of it more as a type of connector. It wouldn't have that much health but we don't have any 1x1x4 armor yet. I could use this and keep connecting the armor points to create a rly cool structure for my helis or planes. If you don't understand it then if they add it then I guess you will just have to wait and see.