OPR vs. Other Ranking Sites

How do players live and die by OPR rankings when they use an estimation for rebuys and add ons. My Poker Tracker shows I have a positive ROI when OPR does not. Some players re buy more often than others. I just see their numbers with estimated RA's are incorrect. I show positive ROI on other sites like Pokerprolabs etc. What do you guys think?

yes, most of the knock out and rebuy game in OPR and some similar sites are not that accurate.

simply because it is impossible to know , who rebuy how many times, and how many bounties u got...

I guess I really should not care. I want my opponents to think I am the worse at the table.