topping dx5

Hi all. I already have topping dx7s and currently pairing it with hifiman sundara and audio technica r70x. The current issue that i have is the headphone amp output impendance in dx7s is really high (10ohm), so i can't use my iem, avoiding to destroy it. I want to upgrade to the new topping dx5...

What is better sounding DAC: SMSL M500 mk2 or Topping DX5? Or maby something else at this price tag?