I purchased Pennington Smart Seed. I spread fresh soil prior to spreading the grass seed and we watered every day.
The seed just never came up. When we contacted Pennington they refused a refund because we couldn't produce the empty bags, although we did have our receipts. If I thought the product was that bad I would have saved the bags.
They then sent up a brochure titled "What do do when you spread grass seed but only weeds come up." You have to question a company that already has brochures like this ready to send to uphappy customers. I would never purchase, or recommend purchase of this product to anyone!