Not as user friendly as it needs to be. When we add new sizes, it invariably doesn't work and we have to ask our developer to fix. A UI/UX update and a bug fix would make this product a lot better.
Thank you for the review. We followed up on this and it seems you have structured your custom fields in a way that requires theme updates when adding new sizes. Please get in touch with our support to let us help fix the issue you are seeing.