Seeing as MXP only came after EU's MXE ban (doesn't affect me), am I right in assuming it a less interesting knockoff?
Well I have only tried diphenidine which came at the same time and it is most definitely no rip-off of (the imho shitty) MXE. I hear this one is a bit warmer than diphenidine itself (whatever that means with a dissociative, the supposedly warmer ones have always been the ones I liked less). In the case of the other drug, it's closest to PCP and I value it for several things over all other dissociatives...
While there's never been a classical "hole" as there is with ketamine, it takes me very very far away from reality on a cognitive level. The experiences are so utterly surreal, that i struggle very hard with putting them into words. It's the deepest kind of mind fuck I've experienced, on par with salvia divinorum and far surpassing everything from the psychedelics realm (which I have had quite extensive experience with as well).
Another very remarkable aspect of diphenidine is that there is next to no double vision which has plagued me for years on all other dissociatives. Finally a comedown that's not completely and utterly unenjoyable. On the neg, it won't just allow you to go to sleep like ketamine does.
If you ever try it, be careful. It can be very morish and the redosing (which often happens right after the peak since motor skills are largely unaffected) has ruined the entire experience for some people. A lot of people feel it's simply too intense, but more often you see them speak of a great deal of dysphoria. I attribute this dysphoria mostly to those people not being able to maintain control of their thoughts and staying reflected about what is going on, since those who made those claims dosed too high and because I have seen some confusion coupled with dysphoria myself on both diphenidine and pcp. To me it is usually extremely euphoric (I remember saying the words "all hail diphenidine" a number of times).
Now keep in mind I can only speak for diphenidine which is similar, but there are supposed to be differences. From what I could gather, diphenidine is the go-to substance if you're into that cold-ass hardcore dissociation shit, while MXP seems to serve better for just getting high without making too big an investment, a property that suits it's fancy acronym. They seem to have a similar flavor though and most definitely aren't MXE ripoffs at all. Structurally they have very little in common.
On the other hand, their showing up on the rc market is a consequence of the huge popularity of ketamine and mxe which are now both not easy to come by anymore for most people.