My results:
Very worthwhile trip; san pedro is my new favourite psychedelic, my weapon of choice in psychonautical warfare. Again, it's hard to judge, but my best guess is, it was about 300mg. Visuals were minimal. Insight and clear-headedness was astounding, but quite different from LSD. I truly went on a journey.
It lasted about 18 hours, with the peak from about 11a.m. to 8p.m. or so. I suspect it lasted longer because this time, I didn't throw up. I took ginger tea to help with the nausea, and this worked a little too well - I had in fact wanted to get the excess cactus out of my system. So next time, I will take ginger tea AFTER throwing up.
My preparation: one big lemon squeezed, plus sugar, orange and mango juice. It still tasted pretty bad, and the consistency was like swallowing sludge, which is why it took 45 minutes to get through the 600mLs. But it was much better than eating it raw. I recommend this method, but boil it down to liquid instead of sludge, and less than 600mLs for that matter, if you can.