Now that we have a Maslow specific Post Processor, it should be the ONLY recommendation for use with Fusion360.
If you read my post (Optimizing the Fusion360 Post Processor for Maslow) you’ll see that we’ve got a good starting point for customization and experimentation.
While he GRBL post processor should work fine now, I believe that this is a function of GRBL compatibility and is intended to ensure that other CAM interfaces than GroundControl can be used.
Hopefully as MaslowCNC improves and us Fusion360 users gain more experience with the combination (of Fusion360 and MaslowCNC) we will be publishing more specific and configurable Post Processor edits, which would ONLY be appropriate via edits to the Maslow Post Processor.