Thoughts on windshield extenders?

[Wheelie]

What are your thoughts on the type of wind deflectors that attaches to the top of the wind shield? How well do they perform (wind, water, visibility, vibrations)? How about durability? Do they ruin the original screen? How about theft - do they really get stolen? Will the mounts for the original screen be able to withstand the extra wind forces put on it? Any other important consciderations to think about?

What would be the pros and cons of just getting a larger wind screen instead and just "be done with it"? Maybe an adjustable screen?

Personally I like the idea of being able to have a short windshield when riding under difficult conditions where visibility over the wind screen is critical. I also like to have a short windscreen when it is hot and the going is slow. It is only when it is cold, wet, or I travel fast that I like the extra protection. I also think that most larger windscreens look terrible on the types of bikes that I have.

Please share your thoughts. If you have any reccomendations of particular makes and models, please share links.

MRA X-creen make adjustable ones in both clamp on and bolt on versions - but I know nothing about them.

I'm getting older, and creature comforts are becoming increasingly more important.

Some specifics:

The bikes I conscider improved wind deflection for is a Yamaha Tenere 700 and a KTM 390 Adventure. The T7's original is quite good for a stock windshield, even for a rider my height (186 cm), but I still want more. The 390 Adventure my girlfriend's bike (175 cm), and is vastly inadequate even for her height.

I live in Norway where most of the main roads has a speed limit of 80 or below, with only a few roads having stretches of uppwards to 110/kmh. On my longer trips I prefer to travel on the slower roads anyways.

In the past I've never really had a great need for wind protection beyond the original set up. I never found it to be great, just decent enough that I could live with it. But, I am getting older with an incresed desire for creature comforts. Better wind deflection would now be largely welcomed - even at 60 km/h - especially on cold or wet days (a lot of that in Norway).
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