Best? It's a tie between Cube Express and the consultants. The biggest challenge we have faced w/ AX is reporting and building a custom report in SSRS isn't user friendly nor is it simple to understand the table structure of AX. Cube Express does an amazing job of reading the relationships and having them ready for you when you go to build.
The consultants we have dealt with, from sales, to training, to support have all been excellent. Zap has done a fantastic job of hiring good business analysts who also know how to build/mentor alongside you. I love the fact that when interpreting some of the report requests, they say "ok, but what does that tell you about this data?" That's an important question that should follow each component in your BI instance: why do you need this report or dashboard? Review collected by and hosted on G2.com.
We haven't upgraded to the latest instance yet. We were in that "this version just came out" window so we were advised to stick w/ the matured version. In hindsight, I would have liked to have seen some room in our deal where the migration was covered if done w/n X number of months. That's not a deal breaker by any means though. Review collected by and hosted on G2.com.
