*Membership spots not really limited!
I haven't been succesful testing iTunes for paramount; if you know of a way I'd love to learn it!
As long as you know the movies url for the digital copy you should be good to go. They give you a choice between the ultraviolet and iTunes copy. You select the iTunes and you can put in the authorization code to see if it's been redeemed.
Jack Reacher example: http://www.paramountdigitalcopy.com/ecopy/selectmedia.aspx?discid=b7b4eff2-b4b5-4303-8121-9e6cc69b2f29
Am I mistaken?