The 440 is more neutral, while the M50 and COP have more bass. If you're including the COP, the DT770's might be worth looking at too. The 80 Ohm version has more bass, but the 250 Ohm version is more neutral. If you really want comfort, go with the Beyers. If you really want durability, avoid the Shures. If you really want portability, go with the M50's.