LOL, keep selling those pick-axes to the miners!
This would seem an attractive option for most developers, who just don't have the time to research and develop their own anti-crack mechanism. And your terms seem more than fair.
You might want to mention what kind of obfuscation steps you take, and if you've made it easy to hide stuff in memory. (i.e. hopefully it's easy to customize so that crackers won't easily come up with some automated solution.)