In your age group and do some HIIT and Cardio Mix. I do not know much about kettlebells, so what is the ROI on it? I know it can be hard to answer that, so just your personal feelings on how it benefited you would help. I am trying to get some weight training added to my mix and that is the reason for my asking.
A kettlebell is just one small piece of equipment that allows you to have a rather complete workout. Once progressing you may need to increase the weight, but still, something that you can easily do at home. There are plenty of exercises available, online and in books. Just my personal impression but I feel I have exercised well after a session.
Obviously, proper weight training in a gym will bring better results but I don't think that this is necessary if all you care is staying healthy and in shape. I just mix it with other sports like running.
Thanks.