I have one of those flex fans. Its Ok, had some issues keeping my motor cool. Never went higher then 230*, I'm running a 160* thermostat and I run about 190-195 in traffic now, was running a 180*. I added a pusher electric fan for traffic, it helped keep it down. I plan on going electric and upgrading to a aluminum radiator in time, currently running a 3row HD old school radiator.