Reddit mentions of YU-GI-OH! Secrets of Eternity Booster Box

Here's my logic (and yes I will include singles). Also by the next set (Circuit Break, links will be well established, buying is up to you!)

• Need exactly one card or deck core? Buy Singles. Guarantees the cards, you get them off of someone else's hands.
  
  
• Want to open a lot of different sets but don't want to buy 5 different packs? Buy the mega tins. Post 2014, the packs have been mega packs composed the last few sets best cards. Not to mention they come with nice promos... usually.
  
  
• Want to get NASTY and just open up tons of packs? Display boxes of Special Editions and Booster Boxes are the way to go. Watch out though, some of those older boxes cost a lot. But some less popular or reprinted boxes cost less. Compare DUEA, a beloved set with still good cards and SECE. Key point: look for the balance between what you want and cost.
  
  
• Want to open a few packs just because your money is tickling you?* Don't.