Harbeth 30.1 or legacy calibre

I owned the Harbeth m30.1 for 6 years and think they are a very enjoyable speaker.
While I wasn't  diisatisfied with the m30.1, I had the opportunity to hear the ATC scm19 and ultimately sold the m30.1.
I was very surprised that I preferred the ATC mids and they had far more neutral and punchy bass. A great little speaker with a lot of pedigree - and ATC make all their drivers themselves.
Perhaps a downside for the ATC is that they require a pretty hefty amp - 100W plus. The Harbeth played well with lower power amps. Neither are difficult loads though. 

I’ve heard both, own one. Audiotroy gives a very good answer, you will be delighted with either it’s matter of you deciding which one. Remember to factor in your decision that you’ll need a stand, fortunately there are available  stands for both.

This is an old post...i owned the Harbeth 30.1 for about 1 year and they were very nice. They were lacking sparkle and efficiency. 10 sets of speakers later i now have Audiovector SR3 Avantgarde Arrete. Highly recommended if you can find them on the used market. 
I heard the Legacy at a few audio festivals and they always sound very thin...not my cup of tea

I am shocked that you would call them thin. Big, rich and full bodied but still detailed in my experience.