Buying cards on the market is a lot cheaper. Yesterday, After reading your post, I decided to buy 2 booster packs, for the first time in a very long time.
Combined value of the cards inside (2 summoners included): $1.34.
Even with the payback and the SP you get, I'm losing quite some money, because I paid $4 for the booster packs.
The chances that you pull a legendary or a gold card are very small, unless you buy 1100 packs. That's about the number to have a guaranteed legendary...
I guess I'll stick to the market place.
Btw, I'm.thinking about selling my extra cards and giving people the choice to pay with Steem or Paypal. Just need to figure out the best way to set it up. I think the fact that Paypal isn't available on the market place is a huge flaw...