o ring are heavyer..have more friktion..so a pover loss/speed lost must be taken vith inn.
.but only against a vell lubed "standart" thain-..a bad oiled standart chain are even vorse friktion...
so if you not get it oiled ,,,, your thain often.
.the o ring are the best
i have big problems, boiling /greasing my thain....faund i got a high temperature grease...it not the best.. to melt in the chain..(.only grease old type thains )..