The developer of RealTurb has offered some insight on the product and its functions. They state that the product focuses not only on turbulence, but also adds realistic speed fluctuations, wind shiftings and wind shears. In the response, RealTurb says that “wind shiftings and wind shears are all done by hand in order to achieve a more realistic result.”
They’ve also provided videos that display the product. Pay attention to the speed fluctuations on the PFD speed tape, wind shiftings on the ND, turbulence effects on the vertical speed, and speed/wind during the windshear encounter. You can watch both videos (video 1) and (video 2).
Lastly, RealTurb is going to provide their Antarctica product for free to give people a chance to test how RealTurb effects work. The news will be posted on their Facebook page here.