It is a complex software with powerful features and tools for engineers.

But it has:

numeric errors,
not all previous documents are compatible with the latest version, so you have to hold version 7.4, 7.6, 7.8, 7.9. It is hell of work when you dont know which document has been opened with which version.

GUI feature is not recommended for complex projects(very buggy).

The poeple from service are very arrogant. This is my personal experience.