I recently bought an Otto Link STM 6* almost on the spur of the moment. I couldn't really see anything wrong with my usual mouthpiece (a Vandoren T35), but I went ahead anyway. I am glad I did. The STM seems more responsive (pp is very easy, and it seems to give me a fuller tone at both ends of the scale. Maybe it is all due to the slightly larger tip opening, but I am pleased with my purchase.