or Cee Baileys in the USA do a very nice screen for the GS check out http://www.ceebaileys.com/bmw/index.html, this company make aircraft windows but most of the staff ride BMW's so they started making screens for GS's & RT's.
The Z Technik ones are actually made in the USA by National Cycle who also make the original BMW screens but to a lower spec than their own, the Z2240 is a dead ringer for the Cee Baileys Touring screen so would probably suit you well.
I've got a Cee Bailey screen fitted now. Got their Adventure one (with Tobinators) but 4" wider and 2" taller. Excellent. Minimal buffeting on head and shoulders. Also stay a lot cleaner now too. Others haven't liked Cee Baileys, but personally i think it's been a good mod. You'll get plenty of other answers too and/or search for previous threads,
I've got a Givi screen with Tobinators, keeps the wind and crap off me head, no buffeting (but does do a nice a la carte), reasonable price too, think it was under a ton from Hein Gericke.
Screens, lights and exhausts seem to account for about half the threads on here so no shortage of experience and opinions.
Happy hunting.
Keep the ONE you got unless your 7 foot tall. If you must make your GS look like shit with no more wind protection buy a biiga wind CATCHER or buy the wonderlick one I`m floggin
Dog
Happy new year