The RWD pad is actually self-made and gets updated depending on the project. So for a bigger project I tend to customise it to match the breakpoints of the respective site etc. I guess I will make the basic version downloadable any time soon. Creating sets / UI kits makes sense and in times of great symbol functionalities in sketch it is easier to reuse them and make team work possible. Over at uiengineering.de we are constantly discussing and wondering where and when it makes the most sense to move from concepts to sketches to wireframes to prototypes and so on. Would be happy to have you on the podcast at some point to discuss these issues. #uienginnering is what we use when discussing the ways to bring teams closer together and collaborate better.