Is it better to use lookup values in Google sheet or in the data Editor in Glide???
Use the Data Editor.
Using a lookup in the data editor gives you instant results instead of waiting for the the lookup in the sheet to return a value back to Glide. You don’t have to deal with Arrayformulas. The lookup column is capable of returning an array of multiple values from a multiple relation. There might be some situations where you have to use a lookup directly in the sheet, but if you can use it in the Data Editor, then go for it.