The sub-bass thump on the ha-m55x's is only beaten by two other cans. JVC sz2000, and JVC ha-mr77x. The driver size on these is very large, and they push so much air its ridiculous. The ha-m55x's have 50mm drivers. Ha-mr77x's have 57mm drivers. The sz2000 have a 55mm driver for bass, and a 30mm for treble/mids. The ridiculous bass curve isn't for everyone though... Although I can say with 100% confidence that they all sound better than the original monster beats. Not the 2013 beats. Those are actually halfway decent... Anyways, go read the reviews for the sz2000 or the ha-mr77x, and read about the ridiculous amount of bass they push. Its almost just funny to see peoples reactions to them. Heck, I use them as desktop speakers when they are at 2/3 volume on my e11 amp.
I'm fairly certain you don't have the experience to say this.