Thinking of putting to rest ESL63 for Harbeth M30.

Any thoughts of putting to rest my ESL63 USA monitor for a pair of Harbeth M30.1 or possibly a comparable Proac? Would be driven by Paoli SOB's, a D150 or a D79. Listen mostly to classical music.... Thanks
I still have my original pair of Quad 57's, which I bought used back in the early 70's, as well as a pair of Crosby Quad 63's, which I bought circa 1990. Although I switched to horns in around 2006 (and love what they bring to the proceedings), I couldn't give up the Quads either. The 57's need to be restored, haven't used them in decades. Although there is life after Quads, there is something about the 57's coherence that is still unmatched.
I replaced my Proac Response 2.5 with a reconditioned pair of Quad ESL 57, The Proac's have been in storage ever since.

Also have a pair of Dynaudio C1. The Proac has a similar sound to electrostats but with much more bass. They served me well, and would consider selling, since I just can't listen to all of these.
I often wonder how many Quad owners have had multiple sets because they sell a pair and wind up buying another and another and ETC. Nothing else sounds like a Quad, especially 63's. Knock yourself out and try other speakers but there is a high probability you would wind up buying another pair of Quads sooner rather than later. Plus, there are many ways that help 63's where they are weak like super tweeters and Gradient subs. I prefer 63's with tubes and the new KT120's are delightful. Have fun...
There are plenty audiophile grade speakers that are comparable to the Harbeth speakers and cost less. If price is no factor than have it all your way. I love Harbeth, PMC, Spendor, Revel, Stirling, and a few more. Even some custom builders do a spectacular job. Keep that in mind my friend.
I swapped a pair of 57s for Spendor SP2/2 years ago. The first thing I noticed was the veil that appeared. I love the Spendors and still run them on another rig. However, I never forgot how good the Quads were. I ended up buying another pair of 57s and they are every bit as awesome as I remembered.