I personally don’t have experience with those putatives so I don’t know. I think there’s something like P83 already in Mx297 - as from what I’ve understood P83 is a disinhibitor, makes people want to initiate. I’ve been wanting to buy some of that myself lately; when I get to testing I’ll let you know.
One of the more experienced users has mixed Mx297 and P83, check out Kimba’s Mx297 thread.
First run Mx297 solo though! Maybe add a little -none later on.