MicrostockGroup

The benefit is pretty much, exclusively, more cash.  The downside?  You may not want your work in a template that someone else can resell, for example.  Or you might be annoyed to find your image on a $200 poster.

To me it is.  A poster is sold purely on the value of the image printed on it.  A book or cd is sold for the content within.  I'd feel worse seeing someone profiting solely from my image, than something that isn't the focus of the product, like a food label, or something.

A good image helps, but I'd say marketing is the biggest factor. I could create a better cartoon character than Mickey Mouse, but it will never be as popular.

In regards to the original post, I used to not sell extended licenses because I worried about it eating into my freelance work and wanted to keep a tighter leash on my images. I was always surprised that more people don't question whether they want to offer extended licenses or not. In the end though, I decided the money was more important than policing my work.

Yes, but the risk (around $100) and the reward (thousands?) make it a bit more annoying if you spot it in action somewhere .

Actually, I never saw anywhere a poster for 200$ or even 100$. But then, I don't hang out in malls, galleries or boutiques I can't (or I don't want to) afford.

When extended licenses were a new thing at micros (and I was independent then) I initially decided to enable ELs at only the sites that paid a decent return to the ccontributor. The (clearly idiotic) idea was that I'd be able to drive EL business to those sites that paid me the best.

It didn't take long to realize that just isn't the way buyers work - they have one or two sites they buy from and you can't entice them elsewhere (in general; exceptional images might be different).

I cringe when I recall turning down an extended license at IS in 2006 because the buyer offered $300 for unlimited print run on a greeting card and $250 was the price then for some defined limit on cards - I thought the increase wasn't big enough and my $60 royalty too small.

I think if you have a side business selling prints or merchandise you should probably not compete with yourself. Otherwise I think there's not a lot of reason to turn down the additional income. When you can pick and choose license types to permit (like BigStock) it makes it easier to avoid the really bad deals (their unlimited options were too cheap so I used to exclude those). IS is all or nothing on license types but you can pick spedific images to exclude.