People That Have Upgraded From Harbeth 30.1s....

lol ,   well , okay , then

I owned the M30.1's for 6 years and sold them after comparing to the similar sized ATC SCM19 mk2.

The ATC has a more neutral and dynamic type of sound, while still having wonderfully natural mids and highs. The SCM19's bass range is significantly more taut and punchy and - while the specs don't indicate it - reached lower in my room. Sounds more tuneful in the lows too, probably due to the sealed loading vs the ported cabinet of the 30.1's. The ATC sounds much more comfortable with bass driven music and at high SPL's too if that is your thing. They don't give up anything with vocals or acoustic music, though a less plush sound than the Harbeths. 
Both very nice speakers, but I prefer the SCM19 by a significant margin.

Worth noting that while the SCM19 has similar sensitivity specs to the 30.1 it sounds (to me) about 3dB less sensitive. Where a 50W amp might be fine with m30.1, 100W plus would be preferable with the 19's. 

@dromme, thanks for telling us why you upgraded from the Harbeth's. Nothing to be offended by at all, as an (ex) owner you would be in a perfect place to know so I am grateful for your reply.

Horns do tend to still split opinions amongst certain audiophiles, but Klipsch speakers though still rare in the UK, were once an important part of audio history over the pond. 

In any case I'm pretty sure that Harbeth, with it's BBC heritage, wouldn't claim to be the loudspeaker for where high energy and dynamics are required such as for Punk or Metal etc.

Therefore it's reasonable to assume that alternative brands like Klipsch (or ATC, JBL, PMC etc) might be preferred by fans of the Sex Pistols, Motorhead, Metallica, System of a Down etc. 

Unfortunately as no speaker is without flaws, its still a question of choosing which compromises you can best live with. Upgrades are often just a case of shifting preferences as I can testify having been through at least 8 'upgrades' over the last 30 years.

@cd318 I can’t help but think you’re being a bit condescending when you infer that it might only be ’Punk or Metal etc.’ listeners who prefer say ATC to Harbeth. These are hardly genres known for their dynamics either.
For the record, a very large proportion of my listening is to acoustic/vocal dominated music - genres that the ATC Scm19’s excel at.
To me they are simply a more neutral, evenhanded speaker than the Harbeth m30.1 - which was a speaker I enjoyed for many years (in fact I’ve owned 3 different Harbeth models over a 12 year period).

I became infatuated with the idea of owning a Harbeth speaker for a while.  I auditioned the 30s but ended up buying a pair of SuperHL5 plus as I felt they were a step up in every way - airiness, neutrality, bass depth and control, realism.
Thought maybe I could replace my Thiel 3.7s with them but no.  I found in comparing them the Thiels did just about everything better than the Harbeths.  They had the beautiful tone, but were just less boxy, cleaner and more realistic, without sounding thin.  So I sold the Harbeths.  Great speakers to be sure though!