I'm a moderator of the Astrogenics forum and get to play with some of the new things Relko is working on.
I've had an Alfa version of Nexstorm running for a few months that registers strikes at over 2500 miles, although the map range only goes out to 1500 miles.
At the moment the change in range is the only difference between the standard Nexstorm and the one I'm using and there hasn't been any new additions as Relko was working on the release of NGX, but there is progression.

I tend to use NSDisplay as the main lightning display on my own website and I also have WASPII on there, which gives triangulated data plots from StrikeStar EU.
As for WXSim, yes it can "learn" by running a comparison program it looks at the past forecasts and compares them to the actuals, then produces a set of offsets to bring the forecast a little closer to the actuals.
There are also a load of personal preference settings that can be altered in the Pro version, things which are fixed in the standard version.