They might be, but without being inside your head I can’t really tell you! :) Your definition of “tight fluid bass” and mine aren’t necessarily going to line up.
The COP is more of a fun headphone than the M50X, and each bass position increases the bass by about 3dB. When combined with their less aggressive treble, they work out to be a much warmer headphone than the M50’s overall especially if you crank those sliders all the way open.
DIY-Audio-Heaven has some good measurements of the COP if you’re interested.
Personally, since you already own and enjoy the M50X’s I’d probably just stick with those and try to buy something wildly different to compliment them instead, but that’s just me. Happy hunting!
