I bought the Alex Super Soft Modeling Dough for my 2-year-old. I am a very "green" mother, very conscious of chemicals and toxins that my family might get exposed to, so I try to minimize exposure as much as I can. With that thought in mind, I was only considering Melissa and Doug or Alex for my son. I own several different items from both brands so I know these two brands very well.
I bought the accessory set from Melissa and Doug, which came with 4 small dough cups. Having both brands at hand, I can positively say that Alex is far more superior to Melissa and Doug.
To start with, Alex dough is much softer when it comes out of the cups. M&D was so hard that my husband had to work at softening the dough for my son to play. Then, within few days of opening the cups, M&D started to harden and crumble. We did not have this problem with Alex. They were soft and moist, ready for molding right away. My son didn't need any help squishing the dough, and started having fun right away.
Another difference is that Alex's colors are much more vibrant, which makes it more attractive for my 2-year-old.
Overall, this is a great product, I would highly recommend it.