Today, I did this comparison of handlebars.1.0.0:
http://jsperf.com/mustache-against-handlebars

Because of the unexpected performance of handlebars I also did another one with handlebars1.0.rc.1:
http://jsperf.com/mustache-against-handlebars/2

I'm not absolutely positive if I set up the benchmark properly. Someone should verify the benchmark code first.