Yubel's not worth it. Bad Aim and Red Dragon Archfiend from this box still get use, but those are both available in a structure deck for 1000 gems. Instead, go for a long lasting meta deck like Blackwing, Dark Magician or Lightsworn.
Ok then, thanks for the advices. I will stay away from this box (since I got both structure decks at least), keep my half decent DM deck and improve it when I'll get the gems, assuming DM won't get nerfed in the future.
About older boxes, I don't regret sphere kuriboh and secret pass to the treasures from ultimate rising. I'll stick to new boxes and use dream tickes for staples in older boxes.