I tried both Airalo and Nomad when I was visiting Japan , here is my review for Nomad.
The experience was overall very good. Too bad the plan did not offer 5G.

What I liked : 
- Although I had to copy and paste my eSIM information manually the setup instructions were very simple and well explained.
- The plan worked well and offered good speeds. I was able to get 69.2MBS download speed and 18.3MBS upload speed while I did my test in Sapporo downtown.

What I did not like : 
- It's a bit unfortunate I was not able to get 5G while 5G was available in Sapporo
- Since Nomad is not a local network, my internet was roaming through Honk Kong (I guess where Nomad server is). It was not a big issue but added an extra bit of latency.

Really smooth experience! App is simple to use and the internet was fast all over Los Angeles. Good stuff

Nomad：eSIMデータプラン

Nomad

Nomad : 平均パフォーマンス

Nomad : 最近の速度とネットワークテスト