I know this is a touchy subject for affiliates but im wondering what is best to use when watermarking content?

Do you think it is more prudent to use a URL, a site logo, or both?

I have to say ive never really given this much thought until now and my gut instinct tells me to watermark images and movies with both the site logo and url but im just wondering what others do, and more importantly, what affiliates prefer?

Regards,

Lee