Affinity Designer is a worthy competitor to Adobe Illustrator and compared to it, these are the advantages:
- It is really cheap! 50$ for a permanent license is a bargain
- Intuitive interface. Almost entire workflow is like in AI, but some features are done differently. Most shortcuts are same as in Illustrator, so switching to Affinity Designer is not a problem
- It has customizable grid with numerous options
- Image export is very detailed. You can export custom slices of your design, with transparent background with no problems. Those slices can be customized further, so you can export one slice in several file formats and dimensions.
- For the most part image editing is non-destructive
- Zoom offers magnifications up to 1.000.000x
- Customizeable UI
- Really great support for importing of PSD and AI files!
- Semi-responsive artboards! You can customize how to objects on artboard behave when you change artboard size. This is a really great feature when creating responsive design for the web and it saves a lot of time.
- Resource libraries - you can create your own resource libraries and reuse those objects even more.
If you are looking for cheaper and better solution than Adobe Illustrator, don't look any further. For a price of a monthly CC you will get a program with permanent license that does most of the tasks even better than Illustrator!