Hi, not sure if this post is too late to help. But I have owned both the Cronus Magnum & Prima Luna Dialouge Premium to drive my 1.7i's. Although lower in wattage, there is no comparison. The Prima Luna did everything so so much better. Deeper bass, faster, detail, soundstage..,the works. Day & night difference for me. I do have a Rel sub that I incorporate (sometimes it's not necessary) and I upped the output tubes to kt88's.
cheers
k
cheers
k