Found past odds verification database here http://www.oxybet.com/epalitheysi_apodoseon.asp?insid=15
So I gave it a try. According to the site it is the past 12 months and most possibly football only (though not clearly stated). Results are 1X2.
I meassured how off was the odd to the actual outcome on average in basis points. So 200 is 2%. The lower the better.
Pinnacle on 1 218
on X 147
on 2 181
Bet365 on 1 343
on X 168
on 2 215
. So much softer on the favorite.
Stoiximan (Greek bookie) on 1 340
on X 355
on 2 394
. Softer overall.
It is easy for me to do this for other bookies on the site and also for specific odds like above or below 2.