Openshift is a great platform to host your web application. I like the the way it was designed, allowing the community to contribute. I like its performance and up time. Another great thing about Openshift is the free account; you start with 3 small gears, 512MB RAM and 1GB storage and unlimited bandwidth which is good enough for a small start-up website.
What's the problem with Openshift?
I find its pricing plan unusual. If you're on FreeShift, you cannot add resources (like storage, RAM, etc).. not until you upgrade to Silver Plan. So from $0 per month, your next option is already the Silver plan which is $20 per month + resource usage costs.
I find this extremely strange why you're forced to have a minimum of $20 per month before you can add resources. It's expensive, where as Digital Ocean offers 20GB of storage space 512MB RAM for $5 per month; only downside is the 1TB bandwidth limitation.
There's already a feature request to add a pay-as-you-go storage for FreeShift but no update yet when it will be implemented.