I finally decided to get two posters (Curse and Escape) after all. I went with the self-adhesive ones from Posterjack, and I must say I'm very happy about how they turned out. I was a bit worried that they wouldn't stick properly, but they do! Here are the pictures:
http://www.flickr.com/photos/22736224@N08/5592020532/
http://www.flickr.com/photos/22736224@N08/5592022986/
(Yes, I have blue and yellow walls in my bedroom.)
Thanks, Laserschwert!