Normally, the lowers don't quite do the same thing, since they do not block the airflow off from coming under the headlight. That is the major source of the turbulence. To block it, you must make your own plexiglass plate/air dam. (I mounted mine on the MS Lowers mounting brackets though.) It makes a world of difference, even over using the MS Lowers. Also, I tried many different windshields before discovering this.
--Tom
