A plus for the Spark: I think owners are doing well vs. the EPA ratings if you look at Fuelly. Several of the reviews from the Mirage first drive event last week say they were able to get close to or beat the rating as well.
UltArc: 60/40 split seat (U.S. / Canada spec Mirage):
http://images.passionperformance.ca/...shi_Mirage.jpg