I actually purchased and opened two of these booster boxes way back in the day (2010-ish)! Before the pricing skyrocketed and it was actually profitable doing this! LOL
Anyway, from the two booster boxes that I opened (120 Packs), I was only able to build two Complete Sets. However, I did pull 3x Charizard from the two booster boxes. I actually graded the Holo Card Sets and everything came back PSA 10 (could have just gotten very lucky there though).
You have to take into consideration that the Japanese Base Set / Booster Packs are the same as the English Base Set / Booster Packs. There are 16 Holo Cards plus 16 Non-Holo Rare Cards per Set and only 1 Rare or Holo per Pack (1:3 Odds of Holo).
I forget the exact quantity of Holo Cards I pulled from my booster boxes; however, just based off the pack-odds, you’re only looking at 20 Holo Cards (total) per booster box.
Oh i thought you are guaranteed to get a holo in each japanese pack up to neo destiny. If there are only 20 holos, that means 1-2 charizards a box based on probability.
I was watching the first five or ten minutes of a booster box opening on YouTube the other day and within like 4-5 packs the guy had already doubled up on a Ninetales.