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


.... what speaker did you buy? 
dhcod
Harbeth m30.2 + dual HSU ULS 15 MK2 subs. 30.2s are not an incremental improvement to the 30.1. Far bigger soundstage, greater delineation of voices, tighter bass. Overall more forward sound. With subs it is a very different speaker than the 30.1 - which I used with subs as well.  
@prof 
Just wondering how long it may have taken you to get the Thiels placed in your room. From reviews it seems they are Very capable but finicky to placement, very narrow sweet spot and power hungry.  The 3.7s are on my short list along with Vandersteen 5A , Verity Parsifals and  Egg's Andra II.

jacksky,
It's completely the opposite:  The 3.7s are one of the easiest to place speakers I know of, their coax design with the special flat midrange (so so no coning around the tweeter allowing full dispersion) provides one of the widest sweet spots I've experienced with very little tonal balance changes, and I have found them easy to driver with 140W of tube power and even 14W of tube power sounded fantastic on them! 

The 3.7s sounded fantastic the moment I dropped them in to my room, and only got better as I played with position to conform to my own tastes.


@d2girls  Have you heard Coherent Audio Speakers? Which Coherent model do you think compete with Harbeth 40.2? Do you think Coherent Audio speaker is good for rock music like JBL 4367 is?