I have a hunch that chances to pull a 5* hero are better if the summon is done with an epic hero token as compared to paying for the summon with gems. I and others were luckier with tokens than with direct gem summons (tiny sample size of course). It would make sense too, as F2P players would stay more competitive that way. I guess it’s hard to confirm or disprove, what’s your experience?
If it’s true, it might make sense to pay for packs including epic hero tokens, rather than summoning with gems directly (even though the packs result in fewer summons per gems).