MXPr is not likely to be an MXE replacement. It lacks the fuzzy warm glow & hand-in-glove biochemical fit (for lack of a better term) of MXE. It does have some loosely similar parameters in terms of hole potential, stimulation, duration, & dosage (but step very lightly with the latter). Research (strictly theoretical, anecdotal, possibly imaginary) in the 70mg range produced noticeable but not unpleasant stimulation with vivid old timey "newsreel" & Super 8 footage style CEVs. No morphing geometric or blob-like visuals. No open eye or auditory hallucinations. Sub hole experience but seemed on the verge.
Again, though, no warm MXE glow or K smoothness, reminding the theoretical subject more with past PCP & 3-Me0-PCP experiences. Which brings to mind warnings of potential manic episodes from extended use and/or higher dosages. I've got nothing substantial to back up warnings of this risk, but past disso research & common sense agree that MXPr should handled carefully in the lab. Baby steps and so on.