I just buy varies seeds and mix them up myself before feeding my budgies.
I used to use more than 6 types of seeds in the mix for my budgies. Now I just ran out of some veggie seeds, so I am down to 3 types of seeds. In the past a few days I am using 40% oats, 40% millet, and 20% canary seeds. This will change as soon as I receive more seeds. You need to understand that birds in the wild are not limited to eat only 1 or 2 types of seeds. By eating a large variety of seeds, they get a more balanced nutrition intake. We might not be able to duplicate their natural diet exactly, but we can still provide a more balanced diet than a single type of seeds.
By the way, I have tried several brands of seeds mix, but I don't find them that special. It is more economical to create your own mix and have the same results.