wind deflectors

How do you rate wind deflectors. Considering a set and came across them or are they waste of money?

it would be a bonus if they stop water dripping in from the roof when you open the windows

http://cgi.ebay.co.uk/SKODA-FABIA-Hatchback-2007-on-wind-deflectors-4pc-set-/200438861126?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item2eab164d46

Quote from the ad:

'Wind deflectors' qualities:

* during the rainfall they prevent the windows from fogging

* especially for the smokers - improved air exchange in the interior

* better visibility due to dirt protection

* enhanced stylish look of the car

* cool looking

* can be painted

* easy installation

* perfect fit

* superior quality

* mounting parts included

* brand new, 2 years warranty

* dark tinted'

Edited 18 December, 201015 yr by fabia55