I hate flex fans. I have a solid five blade non symmetrical fan on now. Sounds like a single prop Cessna goin down the road but it is really moving some air. Way more than the old four blade. I'd run a clutch fan, but I don't have the room.
See, that's why I like electrics. When I don't need my fans, they're not running. Way more efficient without all that parasitic drag. My fans pretty much never run unless I'm stopped, going light to light in traffic, or it's 110°F. And even when it's 110° they shut off if I can sustain 35mph or so for more than a few minutes at a time.
