Before I debate the merits of which air cleaner is the best, I'd like to find out where this idea of getting caught in the rain with an open filter comes from. This is like some kind of urband legend or something. What exactly is supposed to happen if it starts raining and you're running a filter without a cover ?
As to what works best ? That is so connected to your particular build or combination of parts that there is not clear-cut answer. Obviously a Screamin Eagle breather kit is a heck of an improvement from the paper filter in the ham can your new H-D comes with. Is the SE the best ? For a mild Stage I, II, or III set-up, I think it is. Most of these other products are intended for big cams, re-worked heads etc. Stage IV and V motors. The Doherty Power PACC, the Ness Big Sucker, Zippers etc work well depending on the motor. As with everything my mantra is matched parts. My advice would be to go with the late model Screamin Eagle breather kit and you should be fine. You've basically got a stage I motor.
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