The latest clipless pedals from Atomlab are designed for flat pedal riders that want a bit more from flats, because they won't nail you down like proper SPD-style pedals.
They're pretty grippy, even when not engaged, and they have a super soft clip in and release - sometimes you don't even notice it happening.
The key feature is the cleat/pedal cage design. As you pull up the pedals grip harder, which in theory is great for security but, unfortunately, our experience was a lack of definite engagement or release 'clunk', which meant that we were never sure whether or not our feet were secure.
The bearing quality is good, but they will develop play quite quickly as the bushes bed in. This is because the little O-ring on each axle has a habit of riding up over the spanner flats, leaving the pedal bearings with a good 3mm of side play. We'd also like to see tension adjustment for the springs, because it's very easy to pop a foot out if you're used to the action of an SPD or Time-style pedal.