Selling: another interesting case

This is now my third post about seen-by. As I mentioned before, it's a nice concept. Not a single picture on this website is published without the approval of the editors. I see two main advantages here: Firstly, you don't need to click yourself through tons of not-so-good pictures until you find something that pleases your eyes. Secondly, other websites give the selection process into the hands of the users and let them vote for each others work. This can lead to funny behavior among users ranging from chumming up to hating each other because of their actions.
So all this you simply don't have on seen-by, which makes it quite bearable. Now let's get to the point.
It turns out that seen-by folks not only happily present people's work on their website, but also select pictures that would sell well as prints. I received an email telling that some of my pictures got selected by the seen-by staff and asking for my agreement to start a limited edition printed by a well-known fine-art printer/dealer.
I must say that the fact that they already carefully chose what they want, makes it again very appealing to me. On the other hand, I read their contract and find it quite strict. According to this, I would still be the owner of my work, however I would not have the right to print and distribute those selected pictures ever again somewhere else. In the contract this sounds like this (in German):

"...Die Vervielfaeltigungsstuecke der Werke werden in einer limitierten Auflage von 100 Stueck verkauft. Die limitierte Stueckzahl bezieht sich nicht nur auf die Vervielfaeltigung und den Verkauf des Werkes im Rahmen vonseen-by , sondern auch auf jede zukuenftige und in der Vergangenheit liegende Vervielfaeltigung - sei es zu privaten oder geschaeftlichen Zwecken ausserhalb desseen-by Marktplatzes...."

Money-wise the example calculation of my possible profit makes it really tempting. In the very-unlikely best-case sales scenario, an artist might actually be able to make a living from this. So I don't really know how to deal with it.
I have this inhibition threshold that keeps me from putting my signature under something that declares a limitation of my freedom on my own work, but in this case it looks like a great step forward for someone unknown who is still new to all this.
I think I might try this...anybody has ideas, advices, objections?