Parental Control Software

[MontanaXVI]

Ok, I have to ask this since I did not find any solid threads on it anywhere else.

Does anyone know of any good monitoring software to use on a PC? I do not want to hear your political or parental views on why this may or may not be right, I flat out do not care, I just want to know if anyone has used anything, and if so what were the pro's and con's of what software you picked. I came across this site http://www.mi-inc.com/sentrypc.htm and thought the stuff looked like some heavy duty stuff they are selling, but I have never heard of the company or if it is even any good. I am looking this info up for a friend of mine who recently came across some "goodies" that his 12 year old's friend had tucked away under the kids user name on the computer. I thought about the security functions in XP but this is not something I am looking for, I have set up permissions on other peoples machines and just did not like the built in checks and balances in XP, plus he is looking specifically for some other software to do the job.

Thanks for your time and input, again I do not want an ethical debate on "snooping" on the kids, just what software some of you may have used and if you were happy with what it did or not.