Yes, "compatible and compliant", as it is formulated. MyBusinessQuest makes use of a great part of the processes in ISO 15504 but instead of the pure software related processes it uses generic processes.
The duration of an assessment with MyBusinessQuest is much shorter than the time needed for a SPICE-assessment. Therefore MyBusinessQuest is much more efficient than SPICE. But if you have to dispute with the genuine text from SPICE, we recommend to use the assessment tool SPiCE 1-2-1.
As manager you may of coarse perform assessments alone. The value of performing an assessment is additionally increasing with the combination of different opinions and viewpoints in your organization. Whenever a group of managers of different levels perform assessments the varying opinions even in trivial things will show clearly.
If you are satisfied a 100% with you management abilities, then you don't need MyBusinessQuest.
But: "If you stop becoming better, you just stopped to be good."
And MyBusinessQuest helps you and your colleagues to identify your potential as well as the dangerous potholes on your way to success. MyBusinessQuest is used in many organizations to create the right atmosphere of motivation and information to enable changes into the right direction.
Because "Motivation without Information is Illusion"