Harbeth vs Proac

Both lines have a cult following, and sound 'organic'. The stand Mounted Proac Response 2 or newer D2 however have been among my favorite speakers for over twenty years.

I've had or heard both--2.5, Response 3's, 3.8, D25, D38 and Compact 7's, Super HL5, Monitor 40. The sound is not greatly dissimilar but I prefer the Harbeth's. They are more musically natural sounding while the Proac's tend to sound more hifi.

BRM1,

I had the pleasure of owning the M30s for awhile. Now have also listened extensively the c7es3s, p3esr s and own the SHL5s.

I would choose the C7es3s over the M30s. The c7s in my hearing is more musical compared to the flatter sounding M30s. Both still have that harbeth signature sound but the c7s are just somewhat more involving than the M30s.
Ymmv.

I have owned the newest 7's, I liked them, but they lacked the resolution of my Coincident. The midrange, just like everyone else says, is still the best I have heard. I have been thinking about the 30's, because of the better tweeter, but they may not produce enough bass...don't know.

If you find the Compact 7ES3's to lack resolution compared to your Coincidents, it is likely you will find the M30's to exhibit the same, probably to a greater extent. The tweeter in the M30 may be of higher quality and lets more detail through but the overall presentation is a lot smoother and thicker compared to the C7ES3's. The C7ES3 sounds more open, lively and dynamic compared to the M30. The M30 is more composed and shut-in in comparison. Bass performance between the two is almost similar. Judging from your description above, the M30 may not fit your listening preference.

In the Proac line, probably on 2.5/2.8 any thing else is way more than I care to spend. The bigger Harbeth's would be interesting, but I will NOT buy anything with metal tweeters.

The bigger SHL5 is slightly recessed and less dynamic compared to the C7ES3 and will not give you the same resolution and detail you are getting with the Coincidents. The Proac 2.5 is leaner, quicker and more dynamic than the smooth and organic Harbeth. I have a friend who owns both Proac and Harbeth and prefers the latter. There are others who prefer the Proacs. The new D2 brought up by Jaybo can be an interesting alternative to the Harbeth.

To add to the above, electronics play a part in getting the Harbeths to sing to their potential, as usual with most good speakers. Due to the inherent characteristic of the Harbeths in their warm and smooth sound signature, a dynamic amp(as opposed to a smooth sounding amp) can alleviate the perceived lack of resolution, detail and excitement to a certain degree.