MP's don't train their chicas; nor are MP chicas really in the business of giving massages.  Getting a decent massage depends more on the chica you select than on the MP you select.

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You might try Cheaters (on 6th between Revolucion and Constitucion).  If you're there at night tell Erica what you want and ask her to recommend somebody.  

(Note: I haven't been to Cheaters in awhile as these days I date a lot of civilians and semi-pros.  Erica may be at the new place, D'Ellegance(?), on Revoluction.  Both Cheaters and D'Ellegance have the same owner and Erica is his "wife"; she has "clout" with the chicas--if she's willing to use it on your behalf.)  

Few guys ever get to know the receptionist at an MP. Even fewer ever tip the receptionist.  I've found that over time asking receptionists for advice and tipping them when I get what I want pays dividends.

This is the only Place that I know that is a real
Massage place.