JetBrains Rider is a paid application (it starts around $15 a month, and each year it drops – for example, I now pay about $10.00 a month because I’ve been using it for years and years).
It does have a slightly different look and feel from the Visual Studio versions (although you can set things up to have the Visual Studio hotkeys and some of the look. It’s a 64 bit application, which is part of what drove me to it. A large project can quickly overwhelm the 4 Gig maximum address space in a 32 Gig application, especially if you also use Unreal Engine. That being said, Visual Studio Community 2022 is (FINALLY) a 64 bit application.
Out of the box, analyzes not just your code, but also goes through your scenes and prefabs to find instances of your class and useages of your code. It gives suggestions to streamline your code (and automatically supports older as well as newer versions of Unity, so for example, in Unity 2022, it will look at a line like this:
public List<string> someStrings = new List<string>();
and suggest using the newer syntax
public List<string> someStrings = new();
And of course, it won’t make that suggestion at all if you’re in Unity 2020 or 21 because those versions of c# don’t support that construction).
It’s very good at catching codesmells in general.
They also offer a plugin for Visual Studio Community that allows you to use much of their code analysys tools within VSC. I found, personally, it just made more sense to make the switch wholesale to JetBrains Rider, and I’ve never really looked back.
Either Community or Rider are head and shoulders better code editors (though they do have a larger footprint on your hard drive) than Visual Studio Code. We use Code in our lectures because unlike Community, it is available with the same look and feel on Linux, Mac, and Windows, and unlike Rider, it’s free. Since Code is an open source community driven tool (for many languages, not just C# and Unity’s flavor of C#), though, keeping it working with Unity becomes more and more of a challenge as time goes by.