Lots of good comments here. Our experience FWIW...
We spent ~4yrs looking before we bought our now much loved and enjoyed CatNirvana
. Like the OP, the Captain
here was a fairly experienced sailor, including ~30yrs and some (altho not a lot by comparison to others here) 'blue water' miles, but virtually all on monohulls and no ocean crossings.
We attribute the success of our eventual decision primarily to (1) taking our time and sailing on as many vessels as we could and (2) undertaking formal, maritime commercial
training and qualification. If the OP is already happy with his/her maritime skills and experience, then (2) may be optional (altho we certainly gained a LOT of useful knowledge in that step!) but our experience suggests that (1) is a 'must do'. If we had bought a vessel at the start of our search, it would have been a very different vessel...and most definitely not the vessel for the life we now love!
We happily recognize there are lots of great vessels out there...and we sailed on quite a few of them! For us, however, the L440 was the proverbial 'category killer' for everything we wanted...blue water safety
; well designed deck
and rig layouts; good light-air performance; lots of storage
ability in terms of both space and flotation capacity; and very, very comfortable inside. Using the OP's terms and based on our experience now on CatNirvana
(>20,000NM, including crossing both the Atlantic and the Pacific...and the Med, the Caribbean
, and the Tasman seas) we would strongly recommend the L440 as the "best cat for extended cruising
"...for us, anyway.
We wish the OP well in the search. Enjoy the process!!