VRChat is probably the most popular VR destination, with a very large user base and support for not only VR worlds, but fully custom avatars as well! VRChat also works on Windows, so a VR headset is not required!
However, developing in VRChat comes with a high learning curve. VRChat uses the Unity development platform for worlds, and Blender (and others) for avatars.
The benefits of using VRChat over Horizon Worlds include a much larger user base, support on multiple platforms, custom avatars, much better graphics, asset importing, and external linking among others.
By developing in Unity/Blender, you own all of your development work and code and can use those assets in multiple platforms. Horizon Worlds on the other hand doesn't allow import or export of your worlds, so if it ever gets shut down, all of your work will go down with it.
For all of these reasons, I'm beginning work on TRON VR in VRChat, including avatars based on characters from the original film! I look forward to sharing my progress with you soon!
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