String Recommendations

I've enjoyed using Aguila Carbonblack (high G) on a Collings spruce/maple tenor and I've tried 3 different new first strings (from 3 different sets dated 9/17) and each one broke, frayed at the saddle, which doesn't have any problems. Which other strings are closest to Carbonblacks in terms of feel, tension, tone, and appearance? Thanks!

The Martin Premium strings are either the carbonblacks relabeled or a different formulation of the carbonblacks. They’re made by Aquila and Martin puts them on their top-end ukes.