Yes, it's necessary. However, we provide you with one free, slightly outdated version of Navigraph data when you purchase the aircraft. It is pre-installed for you. It is up to you to keep the data up to date if you choose to.  A large chunk thus far has been operator error sans the installer issue, which appears to only be sporadic. Given the number of sales vs. reported installer issues, our success rate still far outweighs the non-successful by a large margin. To add to that, those with minor hiccups have found the solution quickly. That said, I am investigating the installer issue on the few systems it has occurred on and will most definitely find a fix even though I can't seem to reproduce the problems so easy. In the end the decision is yours. Thanks for considering!