2. Real C#
3. Editor Support
Another advantage of choosing C# instead of UniScript is that you can use Microsoft Visual Studio as an editor for the Window platform, or use cross-platform IDE MonoDevelop. Both of these support auto-completion and context-sensitive help.
In the case of UniScript, you may use UnityDevelop for Windows, which is a modified FlashDevelop editor. This also supports auto-completion and context-sensitive help. If you may prefer, for some reason, a plan text editor, then you may use the built-in Unitron editor.
After considering all the above points, then I would advise any programmer or developer programming in Unity game engine to use C# programming language instead of UniScript. This is because UniScript is a new language to most programmers and may take time mastering it. Also, in my opinion, C# gives the programmer a better control and has the best editor support. However, it may be a slightly complex language to master. The majority of Unity3D.com programmers don’t use UniScript, as they find it difficult to use thus opting for C#.