I originally used SliceHost which was acquired and integrated into Rackspace for cloud hosting since 2010. The services is easy use and rock solid with many advanced features. But then again it is a premium service and cost prohibitive. In 2010 I switched to KVM based hosting using vServer Center and still use it today.

Recently, though I still have vServer Center because of the great cost factor, I have started using Microsoft Azure Cloud hosting.

Gen 3 Cloud

Currently (Dec 2016) evaluating cloud services and techniques,

...