Or lets put it this way, the difference between 120w 200 amp is I think is roughly 1db. In every day listening you're never going to notice that, I'd be surprised if in most cases the amp even swings over 10watts. It's more about the energy stored (those capacitors) and being able to deliver peaks when called for.
The biggest thing with your speakers is the ohms with a min of 3 and how often and how long it stays there not all amps can do this. Naim springs to mind in this regard as they specifically list it. eg "able to drive 2 ohm loads for extended periods of time"
But I'm sure you will be fine.
Edit;
Just to add I think you should add a musical fidelity to the list, the m5 model, actually has a little more power and they pretty control everything they have thrown at them.