We’ll thank you so much to everyone who contributed!
My fears are completely allayed now.
I was looking at the Witter WX200, but that has no looking feature and the slightly more expensive Thule has a rather impractical tilting arrangement, you have to put the thing together, but it doesn’t fold away (unlike the really swanky top of the range Thule featured further up this thread – lovely!)
So I have opted for this rack. It’s a “QLP Diamant”, also badged by Bosal. The first Youtube video is a CGI fitting instruction video, but then the second is of a real rack with a real person! He’s a Dutch bloke so i’ve no idea what he is going on about, but one gets the general idea. The bit where he stands on it was the clincher, but this carrier looks really well engineered. It’s compact, folds flat in seconds, includes locks and looks like the easiest to fit and remove. It’s also supplied with a carry bag and you don’t have to assemble it, all for just £150!
[video]http://youtu.be/q0CFDGcvJ3Q[/video]
[video]http://youtu.be/E1Yc_u3utkI [/video]