The salesperson that told you that either doesn't have clue, is making stuff up or just flat out lying. I have owned these for months and they have the same fantastic sound with powerful bass that they had out of the box.
Regarding comfort, I had the same comfort issues at first. They became much more comfortable after a few weeks and now I don't even notice they are on my head.
IMO, THE M-100 IS THE BEST SOUNDING BASSHEAD-CALIBRE HEADPHONE AVAILABLE TODAY FOR UNDER $300.
Ok! I will try then again! About comfort, do you wear specs?
I have the D2000, and I have previously auditioned the D5000 and D7000. I feel that all 3 cans are good for delivering detailed bass that has nice sub-bass definition. Nevertheless, they are lacking in mid-bass quantity. On the other hand, the M-100 is far from a neutral can IMO - it is quite v-shaped, with a noticeable mid-bass hump and slightly extended treble. I don't subscribe to the belief that burning in cans will result in a drastic change in sound, and I believe the M-100's bass quantity isn't going to disappear.
You may want to ask the team at Stereo to provide you with an E11 or ZO2.3 when auditioning the M-100. Try to boost the bass and see if you like the sound then. Good luck!
Wait the denon dxxx series are lacking in Midbass???? Dang I gotta go try all of ten again.
The yklee118 post about the beats pro (which he calls beats professional) seems to intrigued me- Soundstage as spatial as the Ultrasone edition line, that's gotta be something!
Going back to stereo try all over again. I believe that burning in actually help, yklee118 burned in the pros for 600hrs++, I think that's why nobody heard their true sound