Can I use SlingStudio project files with video editing software other than Adobe Premiere or Apple Final Cut Pro?

You can, but it's easiest to work with Adobe Premiere and/or Apple Final Cut Pro.

If you need to import your SlingStudio project files into editing software, we recommend using either Adobe Premiere or Apple Final Cut Pro.

That's because SlingStudio offers file conversion software that works with these two editing products. This conversion software automates the importing process and eliminates the tedious work of importing individual files.

But you certainly can import SlingStudio files into video editing products other than Adobe Premiere or Apple Final Cut Pro. It's just that you won't benefit from the automated project import/conversion that the SlingStudio software utilities provide, so the import process is likely to be a lot more work.