Habitation door stopper

Searching for our new van, and checking out the "competition" I noticed various continental models, that have sliding door stops. Which stops and holds the sliding door, up to the point of the kitchen unit. 
Which offers additional protection from the wind etc. to the habitation.

I have found various websites offering a modification eg 
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Similar available on eBay.

Looks simple to fit and under a tenner so I wonder - 

Has anyone within this forum fitted a partial close-door stopper to their van? 
And to what success?

Thanks

Regards Pete

I use a tennis ball pushed into bottom door runner. Simple, cheap,infinitely adjustable and can put it in front or behind door runner to allow for slight slope if van not level

Bilbobaggins,
Thank you for your quick reply and great suggestion.

Thank you for your other advice "Nil Carboutundum illigitimi",I will definitely take it..

Hi i use a small plastic wedge thing purchased from Ebay you stick it on the rail anywhere that you want the door to stop. Works great i got one for my son's van as well. Kevin