I'm sure the Sander's amp is fine. However, there are many amps out there that will power the Martin Logan speakers quite well. Tube or Solid State.
Find an amp that is well made, and is basically an arc welder and you are good to go.
You can go with tube amps on the upper panels and solid state on the lower woofers and that not only works quite well, it sounds wonderful.
Remember, high power capability does not mean loud. Just like large speakers don't necessarily mean loud.
Listen to a variety of amps capable of powering your speakers and hear for yourself.
enjoy