The main difference between thses two speakers (both are phenomenal performers BTW), besides the SR 17.5 being easier to drive (assuming that you are talking about the Miro Utopia Be), are in the voicing. The Utopia is more "solid-state" in its sound, while the SR 17.5 is more "tubey". Whichever sound you tend to appreciate more, should lead you in the appropriate direction.
