If you are familiar with Ejs5.3 and find it easier to use, it can be a good choice for your remote laboratory project. However, support for Ejs5.3 has become limited as newer versions have been released. Ejs6.01 is more actively supported and includes updated features that improve stability, compatibility, and expandability, which could benefit a remote lab setup.
The main advantages of Ejs6.01 are better performance and additional functionality that may make development and future maintenance easier, especially if you encounter issues or need support from the community. While Ejs5.3 may still function, it's advisable to consider Ejs6.01 for a more future-proof solution.