Currency Conversion!

My partner and I are heading from New Zealand to Japan for 1 month at the beginning of February. I have seen ads for Wise/Revolut App based cards and am wondering what the best way to go about currency conversion is! My currency is NZD but would appreciate any advice with your experiences! Do you have experience with Wise and/or Revolut App-based cards? I see they promote currency conversion so am heavily considering this as my primary option. I am heading over with approx $10k, is it better to convert it all at a vendor over there or convert it using these apps? Really have no idea what the best option is here so would really really appreciate any advice! Thanks in advance

by -soaptastesok-