Statistics by month will tell you what kind of form your opponent is in It gives free information on NL25 and PLO25 for all supported rooms. Statname does not have a free trial version, but you can evaluate the service before you buy it. The database of the service includes NL Holdem and PLO hands.
It works in the browser, so it does not violate the rules of the rooms. Statname collects information on all online poker cash players. The problem is that sometimes you need the information now, and it's the first time you've played an opponent. They collect all the hands you've played against your opponents and give you generalized statistics. The main source of useful data online is poker trackers. If you know more about your opponent than he knows about you, you will win. Information is the most important thing in poker.
