The only differences I've found in various ligs is the response, unless they don't seal the reed to the piece (which is the problem I have with rovners). I've used non-inverted Bonade's for over thirty years. They do a good job, and are cheap. They hold their shape better than some other two screw ligs. I tried both a bonade and a fl. I could tell no difference. I tried the same on an STM, and I found that the stock lig responded similarly. Of course, this goes along with my hypothesis that most of the tonal differences that people detect is a direct result of differences in the attack transient. More research is needed.