If you need concrete, this is a good deal. I just finished an 8x4 slab and costed me a lot using 80lb bags. Now I have another slab that is 8x10 and this sale saved me a lot! I wish I wouldve waited for the same to finish the 8x4.
As far as brand, Sakrete/Quikrete, same thing. If you're that picky, go buy the commercial pre-mixed.