A Go Pro would be good if you are planning on taking action photos or videos. However, I own a GoPro Hero 5 and uhm.. I find that it would take quiet a bit of research and technical skill for me to get the photos and videos to look the way I'd want them to, vs how easy I have it when I just bring my DSLR. Extra weight - yup, extra space - yup, but better than the Gopro if you are looking for something that can do it all. In my opinion, I brought my Gopro for taking videos and pictures when I go diving, but the footage needs too much work, so I end up using my iphone + DSLR on land and I am now considering investing a proper underwater camera for best result.