Just be aware that the sole of a cycling shoe is very stiff to optimize power transfer, whereas the sole of a sandal - even a cycling one, will be much less so. If you don't have a long commute, there are minimal hills, and you aren't looking to set any speed/efficiency records you'll probably be quite happy with them. Just note that you may "feel" the pedal through the sandal, and that your feet may get tired as the arch/foot muscles will have to do a lot more work than when you're wearing a cycling shoe. Set the cleats as far back as you can (I don't know how much if any adjustment is available with those sandals), and treat it as an enjoyable "stroll" rather than a "power commute".
<If you're gonna be dumb, you gotta be tough>
Get Fitter! Proud member of the Smartasscrew, MONSTER CLUB
Get your FIX today?