Mystery Series 3

I was reading an old thread about the Collector’s Store mystery Series 3 card, and everyone was saying never to touch it because it’s hard to get tokens and to save them for Series 4 cards. But you’re more likely to get tokens if you’re series 3 complete, and the collector’s caches are still going to eventually give you Series 3 cards you don’t want. So wouldn’t it make sense to keep getting the mystery series 3 card until you’re series 3 complete and then save up the tokens quicker?