I don't find them very similar at all actually. Other than they're both very strong stimulants and they both work on DA/NE. That's not to say they feel the same in any way though.
I would sooner compare MDPV to cocaine or methylphenidate (Ritalin®). Though it is still its one chemical, with its own effects.
I guess one similarity would be they both cause psychosis relatively easy. MDPV sooner than meth, in my experience. MDPV is much more jittery & anxious, for me. MDPV has a slower building tolerance, but lasts much, much shorter. So more re-dosing is needed to stay high. MDPV feels more compulsive, whereas methamphetamine feels more addictive. Again, this is only my experience.
Never mix the two, I found it frighteningly over-stimulating and taxing on the brain / body.