As stated while the EP350 is a nice sub, it's no upgrade over a VTF-3.
My suggestion is get the Axiom speakers, but not the EP350 sub. The VTF-3 is very capable, but if you want an upgraded sub try the Axiom EP500. Price-wise the EP500 competes with the SVS PC-Ultra, or Hsu TN-1220HO. (Aside: That would be an facinating comparision!!)
You could probably get by with M60s and use the money toward an upgraded sub. However the VTF-3 is no slouch (I have one) so Epic 80 minus the EP350 and keeping the VTF-3 is another option.
I don't have any problem with brightness on my M60s. They are accurate and reveal the recorded sound as is. There is a user-installable resistor option to dampen the highs a little -- call Axiom about that.