We have used WHMCS, Kayako, and Ubersmith.
We currently use Ubersmith because of the tight integration with the client billing and provisioning services for our Clouds (custom code integrated into Ubersmith).
The downside is that Ubersmith is expensive, there is just no other way to say it.
Brent Presley - firstname.lastname@example.org
Innovative Scaling Technologies Inc. - Enterprise Cloud Hosting and Support
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