I don’t believe that 2 M22's with a crossover set at 80 Hz will have the same presence and lower end definition as 2 m60's with crossover set at 60 Hz. This is just physics, a bookshelf speaker with two 5-1/4 woofers can't possibly move as much air as a floor standing speaker with dual 6-1/2 drivers and a single 5-1/4. Even though the M22's can reach 60 Hz, there is now way they would sound as good as the M60's in that lower range. So going the M22 route you will be asking the sub to do more work (the nice thing about the EP500, is that it is more an up to the task).
However, if you are asking your sub to play the higher frequencies 80 Hz, the placement of the sub becomes that much more challenging. That in itself is a reason to go with the M60’s and a crossover set at 60 Hz.
Don't get me wrong, I am sure the M22' is a great speaker (it should be, it comes from Axiom) and the Corvette is a great car, but it's not the McLaren F1.
If you have the room and the budget, get the M60’s, you won’t be disappointed! And if you can, figure out a way, get a 3rd as your center speaker.
