The TW2 SE846 combo is a $1000 combo of the Shure flagship IEM so should sound awesome.
I personally have had zero issues with sibilance on my AZ60
@erockg did you modify the tips removing the foam when you had your pair?
But for
@guitarizt the real question is how do the AZ60 sound compared to the SRH840.
From memory my SRH940 had a nice open sound for closed back headphone. From my research and testing in local shops back in the day the 840 was a bit less open sounding. I think it may have had a darker signature as well. Both models were midcentric in signature.
The AZ60 may have to much bass out of the box but it can be tamed with the EQ. The mids are nice and full with great detail and presence with a hint of warmth. The treble it nicely detailed with good shimmer on cymbals without coming across as harsh or strident. For a TWS I think the AZ60 has a decently large sound stage that bests most of the TWS I owned or have owned including the WF-1000XM3, Sennheiser MTW1, CX400BT, Anker Soundcore L2P. The AZ70 also has a large sound stage but is a more mid/treble centric sound signature which may also be an option for you.
The last option I can recommend is the Samsung Buds Pro. They have only average ANC and isolation but their transparent mode is great and they almost no ear pressure by design. Signature wise they are definitely influenced by AKG engineering with solid but controlled bass, excellent mids, and details treble. The sound stage is slightly smaller than both Technics but not enough worry about. They are very comfortable to wear to the point I can more or less side sleep wearing them. But if you use larger tip sizes be prepared to have some 3rd party tips handy as they have on 3 sizes and the large is on the small side. I use large Sony hybrids on my pair.