Keens fit my feet like no other shoe I've found.  Too early for 5 stars, but so far so good.
As for fit, I've been wearing Keen Voyageurs in a size 11 for over 10 years and love the fit.  I read that these sandals fit a little big, so I ordered a size 10.5.  They were too tight, so I ordered the 11's.  They fit perfectly.
Keen needs more slider sandals to add to their line up.  Durability to be determined as the summer wears on.