One major difference is their user interface and workflow. Maya has a more customizable and streamlined interface, which can be beneficial for artists who work on complex projects. On the other hand, 3ds Max has a more structured and consistent interface, which many users find easier to navigate.
Another key difference is their modeling tools and techniques. While both software offer a wide range of tools, I've found that 3ds Max's modifier stack approach can be more efficient for certain tasks, especially when working with hard surface models. Maya, on the other hand, tends to be more powerful when it comes to organic and character modeling, thanks to its advanced sculpting and retopology tools.
In terms of rendering engines, both software have their own default renderers - Maya has Arnold, while 3ds Max has Scanline and V-Ray. However, both can work with various third-party renderers as well.
Ultimately, the choice between Maya and 3ds Max often comes down to personal preference and project requirements. I've worked on projects where both software were used in tandem, leveraging the strengths of each to achieve the desired outcome.