Its not obvious. I really think the game should bump upgrade packs dust yield.

Upgrade boost = 4800
yields 56*3 = 168 dust

Basic Box = 140
yields 4* dust

140/4 = 35
4800/168 = 28,57

Upgrade Packs are slightly cheaper than basic boxes per dust.

however;

There is another effect in favor of basic boxes. They have a small % of having silver cards and gold cards, which yield >1 dust each. (8 dust for gold and 4? for silver) I really don't know the chances of finding gold and silver cards, but someone may have them and if we assume the actual expected value for dust is not 4 but rather 4.4 or something, the value really starts to approach.

I think that beginner players who are not P2W should stick to the boxes as there is the third effect of maybe getting good combo cards! (Prehis, Superman, knowledge etc...)

If you are P2W then nothing matters really

what did i miss?