PR predictor tools are unreliable. Best to use a PR checker tool such as www.iwantpagerank.com and then deduce what is the likely PR based on the info given.
I think iWebtool predicts the pagerank in an effective manner than others. They are pioneer in this field. That's why I am always checking my sites with them.
predictor, dyou mean this tool will just predict? thats of no use. just test your site to a real page rank checker.