This plugin offered exactly the functionality I was seeking. The installation was easy and it was a real pleasure to discover easy-to-use software that worked first time. On the back of that I purchased the version for the enhanced options.
What really impressed me was/is – other than the software itself - the level of support I enjoyed after deploying on a more tightly configured host (which interfered with image sizing). Timely, courteous and knowledgeable.
If you are seeking this scratch-off functionality then I recommend giving this plugin a try. I am minded that the author deserves users’ support. Please consider also taking the time to contribute a rating and comment.