All comments below are from my experience:
I have used Atlas as a loading tool and as a reporting tool. In each instance it worked very well.
The beauty of the reporting functionality of Atlas 6.0 is the flexibility, there is no rigid structure so the ability to make the data work for you is easily accessible- no long do you need to conform to rigor, with Atlas 6.0 you can finally get creative. However, this is only possible once you learn the tables, this was the hardest part for me- knowing which filters and fields to apply- luckily for you I have documented these within my site (so you can achieve where I had to conquer). The second elegance of Atlas 6.0 reporting is that it uses the power of Excel, so all you Excel Ninjas can use the knowledge of your advance Formulas and formatting to build a report that would get the envy of even the best Management Accountants.
The loader allows large sections of data, including Exchange rates to be ‘loaded’ straight into AX 2012, this saves time and creates organisation efficiency- what more could you ask for!
Useful Atlas links: