You're not thinking of using it stealthily are you? Come on... having to hold back is such a terrible shame to do on something like this.
Proscaline is apparently a bit more easygoing and less deep than mescaline, but still I would not forget about the possibility of crying tears of joy out of the blue - having your soul touched - being reborn through lightning.. things like that.
And no the vomiting isn't done casually either.
I wonder myself about plugging or IMing mesc and its analogues, but havent tried it yet. It may help with part of the picture like body load or vomiting, but probably not all of it. Snorting sometimes makes matters worse for a while, depending on the compound.
You are making me wanna do mescaline over the holidays, but not in a stealthy way.