Herbal research often of 'higher quality'

A study published last year in the Journal of Clinical Epidemiology looked at over 80 clinical trials in Western phytotherapy and compared them to similar trials (matched in size, power, scope, and results) in conventional medicine. It's often believed that trials focused on herbal medicine are of inferior quality, relying on poor methodology, and therefore less trustworthy. Of the studies analyzed in this review, over 20% of those focused on herbal medicine were deemed of 'higher quality', while only 5% of those for conventional medicine met the same standard.
While this is not conclusive proof that studies on herbal remedies always have better methodology (see this correspondence for an good opposing viewpoint), it does at least make us question the validity of the mainstream rhetoric that always portrays herbal science research as inferior and therefore unreliable.