I have several pair of Keen slip-on shoes that I use for business travel.  They work well, but they tend to be heavier and (compared to other shoes) bulky.  So I was intrigued by the Keen bleecker slip-on when I first saw them. I wasn't expecting them to match the protection and padding of other Keen's, but could they do a nice balancing act?  Recently I finally decided to spring for a pair to see.  Thus far I've found them much more comfortable than expected.  The uppers are leather and don't have any padding around the foot opening, but the leather is soft enough that (with socks) it flexes and gives to provide a comfortable fit.  While there is less "box" around the toes, the leather upper is thin and flexible enough that there is good toe space, even for someone with a couple hammer toes, like myself.  The insoles are not removable, but in combination with the sole they seem to provide good arch support, though someone with high arches might not feel that way. I found standing and walking in the bleeckers is comfortable.  Appearance wise, the black is ok for business casual and (when traveling) dress use. For travel, a shoehorn is needed to put these on (or I use two fingers).  But they are light enough you can pack them easily and wear another pair if you prefer.  I liked these well enough I've ordered a second pair in the brown for casual use.

Update after a couple of days of wearing for work: Didn't really need any breaking in before I wore all day at work.  Definitely feel different than other Keens that are not part of CNX line.  At times I was reminded of the way sandals feel.  Very comfortable.  Only occasional irritation was that my pants occasionally caught on back of heel while walking, but that is due to length of pants and difference in height o heel, not really the shoe.  As these stretch a bit with use, I'm liking more and more how these feel and look.  And at the end of the day, my feet don't feel quite as tired due to these shoes being noticeably lighter.