Never tried any of them. Could you please explain how Cloud9 and Nitrous.IO were superior? For the speed concerns, doesn't your browser being a thin client with a cache solve those problems?
Here is one reason Nitrous.IO is superior. I could actually run the php file that was created automatically on the box. I cannot do the same on codio.
Another reason is that Nitrous.IO has a desktop client that uses unison to keep files in sync. This means I develop locally using my favourite IDE and I get to preview it instantly on my nitrous.io box, I say instantly but I'm sure there is some latency, but I'm lucky enough to have an internet connection where CTRL-S, ALT-TAB, CTRL-F5 results in my newest code being ready without having to wait.
Sorry but I was hopeful that Codio could live up to it's claim, but the fact I can't even run their default PHP file is pretty sad.
There is a good reason for the PHP not working out of the box. With Nitrous you have to choose the type of Box you want - in this case, it would be PHP. But with Codio, a Box is a Box with everything you need. Which means you are not restricted as to what you can use it for.
Check out the docs on using PHP in Codio https://codio.com/s/docs/specifics/php/, but it's a simple matter of `parts install php5 php5-apache2 && parts start apache`, and you're up and running.