AFR from datalogs on my Flash Pro, simple really.
"the biggest determinant of the map quality is the skill/expertise and prior experience of the mapper rather than there just being a dyno in the equation. Yes, a dyno can be a useful tool, but a highly skilled and experienced mapper could probably produce a better map via an etune than a someone who was merely 'fairly competent' at mapping and who used a dyno. Of course, the ideal scenario would be to have a mapper with superb skills and expertise who also has access to a dyno"
You're driving on the roads 99% of the time, not a dyno, real world driving vs optimised dyno showoffs etc.
That said, you cant tune ignition without a dyno. I'm sure if I went to Eurospec they might make a few gains over my current map but they would not be worth the money it costs to have it done. A lot agree that it's best to have both, dyno and then AFR on the road.
For me I just wanted a 'safe' map to run for a while, I may get a dyno one done as well but I'm not convinced I'll be happy with the outcome over £. I'm not saying one method is better than the other, both have their advantages.