After from what I've seen, yes. Only because the fact if someone lags out at the boss round of the Arenas where you can earn Etheric Light, you cannot get them back or a replacement, so all of that time was wasted and you have to start over. (Providing it doesn't happen again.) If Bungie chooses to fix this problem, then no, Xûr should not sell them. If this problem persists, then Xûr should sell them, but at a high stake. In my opinion, 25-35 Strange Coins for 1 Etheric Light sounds good. Maybe even 40 Strange Coins for 1 Etheric Light. Call me idiotic for that amount, but I agree with others on this post that this game should be more of a challenge to hit 34. Then again, I've seen someone at 34 already in the first day.