I personally witnessed a before and after dyno of two of my cars on the same day (M6 and M3) there are gains... Must be the old english air
While the gains are minimal, its incremental hp; couple the scoops with filters plus a pulley and you got yourself some decent whp gains for cheap money IMHO.
No one should ever hope that scoops alone will be end all to mods but dollar per hp the value is seriously strong.