Without correct jetting any map is next to useless.
But, with good jetting, the map can seriously improve drive-ability.
The original map I made was very good - amazing performance - but there was always an issue with low speed drive-ability...
After some 'interesting' tests, driving around with the laptop on the passenger seat providing direct feedback on the map, I worked out where the issue was, and have since modified the map.
The results have been a great improvement in low-speed drive-ability.