Ignoring laboratory detergents like Tergajet, would you say that the choice detergent is still very significant?
I get the best results with Cascade Platinum paks, so I buy those. I have had inferior results with other detergents. (Kroger has a clone of the Platinum packs. I think it's pretty good as well, but I don't remember.) So I don't buy those any more, I buy the one that I know will work.
It is not a surprise that the paks work well. There are several ingredients that "like" to be formulated as powders, and several ingredients that "like" to be formulated as liquids. The paks can contain both. This is not possible for pure powders or gels, so that lets paks have more different cleaners in them. (I don't know what's going on with gels. I've never personally had good luck with gels.)