A bit late to the party but I wanted to chime in. I just got my Kiwaya KTS-7 yesterday. It came with the stock Fremont Black Line strings which I thought sounded way too warm and mellow for a soprano, and the loose tension is definitely not for me either. I quickly switched to Living Water strings and immediately thought they sounded way better and more jangly as a soprano should imo. No doubt Worth strings will sound good as well. I want to try regular Martin fluorocarbons on it some time but for now I really dig the Living Waters. Shame she wasn't a fan of the soprano as Kiwaya seems to be a really good quality manufacturer, but hopefully you can take it off her hands.