It’s more like a slam dunk difference rather than upgrade to me. Best if you can listen to the M30.1 before taking the plunge as it sounds quite different from the C7ES3. Although the M30.1 is technically a superior speaker, I prefer the presentation of the C7ES3. With vocals and small ensembles the 30.1 may have the edge though, sounding richer and more lifelike than the C7ES3.
Donjr - similarly I find speaker stands to make a difference on Harbeth speakers. I have tried heavy 4-pillars with top and bottom plates (24" and 16") and lightweight open-frame stands(17"). The SHL5 Plus sounds different when placed on all these stands. Intrigued by your remark on the Q Bricks, I went over to the Skylan site to check these things out. I would have to say, the description of the Q Bricks is rather rhetoric, "vibrations are completely annihilated". Who would have expected the Q Bricks to make the speakers sound like someone covered them with a blanket when they are supposed to open up a new soundscape.
Donjr - similarly I find speaker stands to make a difference on Harbeth speakers. I have tried heavy 4-pillars with top and bottom plates (24" and 16") and lightweight open-frame stands(17"). The SHL5 Plus sounds different when placed on all these stands. Intrigued by your remark on the Q Bricks, I went over to the Skylan site to check these things out. I would have to say, the description of the Q Bricks is rather rhetoric, "vibrations are completely annihilated". Who would have expected the Q Bricks to make the speakers sound like someone covered them with a blanket when they are supposed to open up a new soundscape.