Flows are real step-ins: one can easily reach down and lock the highback while gliding away from the lift. Gotta be careful though, because the latch sometimes catches your glove so you find yourself locked in a crouched position, head down, with one arm in your back. Not a safe way to ride.
About the Flows: My NXT-FX'es are stable and responsive but they kept disintegrating (daily) until I replaced each bolt/nut/washer with real-world sturdy self-locking hardware and fabricated aluminum side plates to replace the original brittle plastic contraptions. Since then it's been A-OK.
I have a set of Catek FR2 Pro Ltd on order. I may end up combining the two pairs into a set of Frankenstein Catek FR2 step-ins !!!