When comparing Eclipse Che vs ShiftEdit, the Slant community recommends ShiftEdit for most people. In the question“What are the best cloud IDEs?” ShiftEdit is ranked 7th while Eclipse Che is ranked 8th.
Specs
Ranked in these QuestionsQuestion Ranking
Pros

Pro SSH + terminal
Built-in terminal with root access so you can make changes to your running machines. Being able to SSH into the workspace so you can use a desktop IDE is handy.

Pro Custom commands
You can package up custom commands with your workspace and then use them (or share them) with everyone else.

Pro Docker runtimes
You can choose from pre-configured environments for Java, Javascript, C++, PHP, C#, etc., or you can define your own by dropping in a Dockerfile - makes it easy for simple and complex projects.
Pro GIT and SVN VCS support
Projects can be easily imported from any Git or Svn repository hosting service.
Pro Reproducible environment

Pro Portable workspaces
The workspace in Che includes project sources, IDE and the runtime. So if you hand your Che workspace definition to another user and they execute it they will get everything they need to build, run and debug the project.
Also the runtime is in a Docker container so it will work even if the second user is on a different OS than the original user who shared their workspace with them.

Pro Previews
Che does a nice job to automatically map the service:port running in the Docker container (e.g. tomcat on 8080) to the Docker port it actually uses (something in the ephemeral range). You never need to figure that out - it's just made available when you run your server.
Pro Merge tool for VCS

Pro Open-source

Pro Low cost, high quality

Pro Revision control
Pro Syntax checking
Highlights syntax errors and automatically fix some errors
Pro Supports multiple file access points
Access files from FTP, SFTP, WebDAV, Dropbox, Google Drive or Amazon S3
Pro Supports autocomplete
Code completion for HTML tags, CSS and PHP code assist
Pro SSH support
Allows connecting directly to a server and run commands on that server.

Pro Good Customer Support
Help requests get answered quickly and successfully.
Cons
Con Slow runtime
Online IDE is much slower than desktop one.
Con Expensive
Con Not user friendly
Con Non free/libre (proprietary)
