Safe to install Visual Studio 2015 Preview side-by-side Visual Studio 2013

I never had issues to install and use different versions of VS side by side.

Its about Visual studio 2015 Release (should be fine for RC also) Microsoft says "You can install and use Visual Studio 2015 alongside Visual Studio 2013 and Visual Studio 2012. It can also be installed on top of Visual Studio 2015 RC without having to uninstall RC"

https://www.visualstudio.com/en-us/products/visual-studio-2015-compatibility-vs.aspx

From what I have read there is potential for things to break: https://stackoverflow.com/a/27040641/3710110

But the 2 can co-exist on a single machine quite happily. I am going to take the plunge tonight. I will come back let you know how I get on. I am running VS 2013 Update 4 on Windows 8.1 OS.

UPDATE 2015-03-16 I have been developing mainly self-hosting web applications in VS 2013 for the past few days with VS 2015 CTP 6 installed on the same machine. I have not ran into any showstoppers so far :)

Yes, different versions of Visual Studio work fine alongside each other. I have 4 or 5 installed right now. New versions don't interfere with older ones, because that would prevent developers from maintaining their existing code base without forcing them to migrate to the new IDE.