Well, for those that are doing enough to get daily medal rewards, I just bothered to check and saw a fair enough goal. 100 medals can be traded in for a stack of 10 card reveals. Now that doesn't sound half-bad to me. 35 medals from consecutive wins and 10 medals per day on daily wins (35 and 100 wins a day per 5) to get at least something worthwhile from this stupid currency before they just delete any you might have gathered at the end of the event.