If you are new to PPV and don't have $500+ spare to invest in testing over and over what works for you best (& learning in a way) then I suggest don't bother. But if you do have experience in the field or know of someone who does ready to give you personal coaching then go for it.
Bottom Line - If you know what you are doing in PPV then you can surely make huge profits of it.
Hi XC, since I don't know anyone doing PPV, what would suggest as a good training course or ebook?
I read some good things about PPV Traffic Assault by Mark Stafford, have you seen his course?
Like the OP I'm not sure if his course is still valid as I believe it came out in 2011