He's saying the the EP175 won't add that much bass extension to the M50s. But the package you're describing is called the Epic 50-175. Though, if you have a little bit more cash, or if the Dollar is weak that day, it would be recommended to step up to the next sized sub with the Epic 50-350 package. Still, 2109.95 USD is 1505.70 Euros today.

Pioneer PDP-5020FD, Marantz SR6011
Axiom M5HP, VP160HP, QS8
Sony PS4, surround backs
-Chris