After we released AceSEF, we recieved too much questions asking about why we needed to develop a new SEF component because of there were great SEF components avaliable. Well, yes, there were SEF components but they either were just generating SEF URLs (sh404SEF) OR didn't fullfil the needs (JoomSEF).
Here it is the comparison table of the most used sh404SEF and JoomSEF components versus AceSEF.