Just wanted to contribute my experiences with 3-Meo-PCP, despite the way things ended up going this is still one of the most profound, useful substances I have used and I hold no enmity towards it (that is reserved for myself).
I ordered 1g MXE and 500mg 3-meo-pcp last october. While at first I was mainly using the MXE (imo a much more recreational substance then 3-meo), after my first experience on 3-meo-pcp I could no longer ignore it. That first experience remains one of the single most profound, mind altering and generally positive experiences I have had on a drug. I have always found that dissociatives (when not overused as I'll get to) are very useful for cutting through the crap and leaving one's thoughts in a more stark, honest form. With lower doses of 3-meo (ie less than 10mg), I found it to be a very clear headed dissociation that allowed me to have complex conversations about a variety of issues, which, when one is dissociated from their ego in some capacity, are very useful.
While I never did more than ~15-20mg at once, I would almost always redose once or twice (usually twice), bringing the total up around 40 or 50mg. At higher doses, the clear headedness disappears and the absolute mindfuck that is 3-meo dissociation appears. At these levels I would completely dissociate from my body (while lying down), as well as my experiences (I vividly remember not being able to remember what my family looked like, or dogs (not just my dog - any dog)). The 3-meo euphoria at these levels can be entirely overwhelming, an all encompassing mania. Visually, well, dissociative visuals aren't easy to describe, one notable effect I remember is after a hit of a waterfall bong, everything immediately seeming to speed up to the point that I had to just lie down and close my eyes. Another time I was playing Dragon Age: Inquisition on 3-meo and at some point stopped being able to differentiate between myself and the character I was playing as in the game, and I started personally becoming worried about events in the game as if they were real lol.
The alternative side of 3-meo-pcp comes when one is overusing it. I had two months doing 3-meo/mxe 3-4 times a week (I know, not as bad as some) and by the end was having trouble properly speaking (tripping over words (similar to but to a much lesser extent than while actually dissociated), as well as (most frighteningly) having delusions of grandeur. I also had many times where I was far too strung out to enjoy myself, and could only sit on my bed at 3 or 4 in the morning unable to move or think straight or anything. Experiences seemed to melt into the next, so that everytime I was dissociated seemed to be picking up where the last experience left off, and on numerous occasions I would suddenly come to my senses during the middle of being dissociated and have no clue what period of time it was anymore.
As far as combining things with 3-meo goes, I would almost always combine weed with it, as I do with everything, though at lower doses of 3-meo weed will cause the clear headedness to go right out the window. 3-meo and whippets, as one might expect, is mindblowing, resulting in complete dissociation from oneself. 3-meo and DMT was, odd. The addition of 3-meo made the breakthrough experience more alien and foreign feeling, and while not bad, I wouldn't count this among the best things to combine with DMT. With 3-meo-pcp and MXE combined it is hard for me to distinguish between the effects of one or the other trying to remember back, but I never remember any issues arising.
All in all, 3-meo-pcp was one of my favorite drugs from the very first time I used it. It's propensity for allowing one to make insights about their life and the world is very useful, and its euphoria is out of this world (and your body). Despite this, 3-meo skewed my thinking enough with continual use that I began neglecting to take care of my life, as the delusions of grandeur convinced me it didn't matter anyway. When used responsibly, I believe this to be one of the most interesting and deep substances I have tried, so interesting and deep that I became unable use it responsibly, and for that reason I would advise anyone who has the desire to try this to remain constantly on the alert for delusional or unrealistic thoughts; alternatively, keep use to say once a month and I would bet on 3-meo improving one's life. I last took 3-meo in early january, and since have never felt any cravings for more, only using dxm (in terms of dissociatives) in much lower relative doses a couple times a month.