I am using YARPP for quite some time and I am very satisfied with the algorithm if properly configured. Related entries are, if the threshold-level is set high enough, indeed related. AFAIK no other plugin matches this rate of accuracy as YARPP does.
Since I have already more than 2000 entries on my blog, and it nowadays happens more often than not that I link to my own entries (for reference, etc.), I thought it would be great, if YARPP could pick up internal linking as an option for relatedness.