Considering that I buy packs, as well as work the market to be able to buy packs, I keep any LS diamonds that I get. My goal is collection, and if you start selling off diamonds to buy packs, you'll wind up with nothing. Later when packs aren't really returning anything, I'll switch to working the market to buy the cards that remain. I usually buy 50 singles every two or three days; just pulled Yelich this morning.
For me, it's more fun to pull cards I don't have out of packs, than just buying them off the market.
I
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