I've been in this same boat before - whether to copy protect or not. It's true that just about any software these days can be hacked so it's often better to focus your time/effort on product improvements and supporting your customers. On the other hand, you do have the right to protect your work, at least to the degree where it prevents honest customers from tempting to be unfair. A quote that sums up my feeling: "Make it annoying for the hackers, but as unobtrusive as possible for the users".

To more specifically answer your question - I recommend Easy Digital Downloads (EDD) and their Software Licensing extension for managing licenses and updates. With a coupon code, it's relatively inexpensive (especially compared to some other popular options) and it's easy to integrate. The author, Pippin Williamson, is a real all star in the community. I can attest first hand at how him and his team stay on top of support issues while also rolling out product improvements.

For tying into JVZoo, EDD also has a (paid) extension for that. I haven't used it firsthand yet but I know of other using it without issue.

Anyway, good luck with this - and feel free to PM me if you have any specific questions or need a hand