I heard a speaker at a conference say that Sass covered a lot more of the weird CSS edge-cases than LESS, can anyone comment on the validity of that? I've used

I heard a speaker at a conference say that Sass covered a lot more of the weird CSS edge-cases than LESS, can anyone comment on the validity of that? I've used Sass in Rails but I wouldn't be opposed to checking out LESS if there was a compelling reason to.