I have been using Evah Pirazzi viola C strings now for several years (along with Pirazzi D and G, and a Larsen A) and have found them to have more power than the strings I used to use. If you are middle aged or more and grew up using metal wound gut strings, you undoubtedly tried to transition to synthetic core strings at some point. The transition was very difficult for me as the synthetic core strings activated differently than the gut core. It wasn't until the release of the Obligato line that I was able to find strings that felt familiar. When the Pirazzi line was introduced, I tried them and loved them and never switched back. As a professional orchestra player, I need to be able to count on my C string to deliver a powerful sound and the Pirazzi C string has that power, and can be played softly with no dropout. When they are new they set quickly, then last a good amount of time before needing to be replaced. In addition, the C (and the D and G) have a nice, warm sound. They are also soft and comfortable under the fingertips.