Well lead purchasing is a sure way to get reported for spaming unless your using a lead that has never been mailed now that is a gold nugget lead ? Most leads have been sold to hundreds if not thousands of people and by the time you mail them the complaints are piling up at the servers. So how much is a quality lead $25 $50 or $100 each and you order says 5000 which is not a lot that will cost you wow yes megabucks with ROI lighty to be in the red.
So by all means purchase leads if you have proven results and the mlm company your promoting gets no spam complaints.
If not avoid avoid avoid and use lots of other methods to get leads.