Supporting your decision there is a couple of factors that might help you in finding the best fit for you and your business needs. In general a cloud solution in most cases (looking with a real assessment at the fully-loaded costs) is the lower cost solution in today’s economy. The economy of scale of a partner-provided cloud will be more efficient to be managed and at a better service level than an own operated server. Also, the skills are a significant factor – running a cloud platform is a continuous process and the people doing that can do this for multiple customers in a more efficient way. On the other hand, a cloud service also has to have restrictions to keep the cloud offer stable and thus will offer reduced flexibility (private cloud or managed service excluded). Also, a cloud service will offer you less integration capability like no direct access to a systems database etc.
In any case, the choice you make is neer final. SpiceCRM offers you the full flexibility to install and run the exact same system on site. So at any time, you have the chance to move a system from the cloud to on-premise and also from an on-premise installation to the cloud.