see if the lbs will let you borrow an arione or ride one on a trainer. I just went out on my singlespeed and forgot how painful some saddles are (looks like I'll get an arione for it as well).
also, some lbs have decent saddle return policies. the only catch with an arione is the wing flex break-in slots. but it takes awhile to break-in so you could probably ride it for a few weeks and return if you need to.
try some crappy saddles first on their trainer bike or sizecycle, then ask for an arione, just for an immediate comparison.
check this article out, it explains how the arione works
BikeSport Michigan " Saddle Breakthrough: Fizik Arione"
saddles are a personal thing though, you might not like it