NOTE: PLEASE USE ONLY ENGLISH IN THIS COMMUNITY
The biggest advantage of having extended license is you can edit the customer and delivery app as you wish and can add functionalities. Easy to do any customization
If you have regular license also, you can customize, but very limited customizations like name and colors.
Also note that, support is same for both regular and extended license.
I suggest you to buy regular license if you are not a developer or starting your business as a start. Once you understand all the workflow and willing to expand you business with more features than what author gave, you can move to extended license.
I hope you understood