Stat met percentage is irrevelant really, it is just a planning figure.
Out of interest, when you hover over the 'target' and get your dist and ETA, what wind does it use? Current wind component or current wind speed? Does it take into account the possibility of a wind change enroute to the div?
WHilst you can measure and then check the AP manually, doesn't this defeat the object of having a computer do it for you, the whole idea is to reduce the workload. If you are having to manually calculate to cross check you may as well use RAPS. Also, as the modern systems are more accurate than the manual crosscheck, the AP will always be different for the 2 cases, which one do you use, what difference really counts?
All issues that both system have encountered so don't think I am only picking holes in the 310 version, the 330 will have the same problems.