Read through the messages everybody has so their favorites. Oxypowder is the only one I use. It is a real cleanse and it does not take months.
You will find different opinions about everything since there are different protocols people use.
I follow mainly Andreas Moritz and this is his view on it. Read the whole thread. //www.curezone.org/forums/m.asp?f=337&i=12699
And this is from someone that likes Oxypowder //www.curezone.org/forums/m.asp?f=193&i=157
Also check the messages that say Colonix that is a fiber product, some people prefer that.
For general info read the FAQ at top of page.