Uhm, yes, the lows do overwhelm everything in M2s. That's why I needed to equalize them. The key word is "needed". R07 are pretty decent without eq, but they do like the high frequency boosts that counters some general high frequency rolloff which is more apparent with silicone tips than foams, suprisingly. Boosting subbass is also nice - they have the capability to be linear down to 20 Hz with proper seal.
M2 can go down to 18 Hz, but need more eq overall, both the bass cut (more by 3 dB and also wider), the sibilance cut (also 3 dB and wider) - and they're less extended up by >1 kHz, which is pretty noticeable difference in clarity.
Plus they're nowhere near as comfortable due to large nozzle diameter.
The sibilance of R07 seems to vary from pair to pair by some dB - one pair had annoying amounts, the new one has some 3 dB (50%) less of it.
Specifically, R07 are like tamed M2. Quite unsuprising, since these were designed by the same company (VSonic used to be called Visang; Brainwavz M2 is tuned Visang R03.)