For in-game currency. Still the extended Box? or that holiday pack with the guaranteed Legendary and Exotic? 8k gold seems pretty pricey, but the guaranteed 'big' runes seems worth it. I'm not a smart person when it comes to money, like as not I'll eventually drop a few bucks on aiming to get my FW 'empties' filled from Planar Disturbances...
The premade Ferren deck has the highest shard conversion rate out of everything in the store (calculations here). If you're going to buy something with gold, that would be your best bet if you're looking for pure efficiency, and it's half the price of a holiday pack.
Yeah, pretty much just looking for highest shard return. I've got an awful lot of holes in the collection. I know the Extended box has the biggest number of runes, but pretty confident I don't want to gamble on those holes filling in through that metthod. Also pretty sure that if I end up sticking around, real cash will end up being the best way to get what I want from the non-forgeable runes, and that makes me sad. Foolishly I went and bought four of the Ferren deck. Looking closer at the checklists, I pretty much need to buy two of each before I start doing 'efficiency' buys. Oh well.