From reading a crap ton of impressions, Is it safe to say that a good planar headphone/speaker >>>> Dynamic driver?.
You can no more say that than you can say a pickup is better than a sedan.
I am a long time planar speaker user, owning various Magnepans for more than 25 years. They do some things wonderfully (open sound, boxless, presence), other things not so well (bitch to set up, take up a lot of space, power hungry, limited dynamics). It is all about tradeoffs. Planar speakers do some things better than dynamic speakers. Horns do something things better than planars and cone speakers. Over time with each of the three major designs (planar, cone, horn) manufactures have managed to hold on to their benefits while lessening their detriments, making each closer to the other over time. The bottom line is like everything, each has its tradeoff, pick which tradeoffs work best for you and enjoy.