What is the best amp setup for Magnepan 3.6 ?

I am the proud owner of Maggie 3.6's currenty getting juice from a Rotel amp and preamp. I am considering some offerings from Odyssey, Monarchy and McCormack. Since the first two offer both stereo and mono versions, which would be a better setup? Would bi-amping give better results than running them mono? If bi-amping is the better choice, can you use two stereo amps or do you always have to use four amps? Did I mention a suitable preamp as well? 5k budget. Thanks.