Two extraordinary choices! Clearly a First World Problem! From 30,000 feet know that J/Boats very cleverly massaged the wildly popular J/40 into the J/42, and the absolute monster rocket ship J/44 into the best of all worlds J/46, a far more versatile platform.
I think I might be able to add some things to the discussion....
Bernie has made some good points, but a few are a little off.
SCRIMP vs. Balsa. Up until around 1992 TPI used what's now known as "pre-SCRIMP" construction, and changed their assembly to embrace the SCRIMP process. Having been very active in the J/105 national class for 6 yrs on their Board, this change happened well into their boat's production run. The result was the creation of two slightly different boats, not ideal with a one design class as highly competitive as this. It's a given that the pre-SCIMP boats are faster due to the hulls being slightly stiffer and slightly lighter, to the point where these early boats are trading quite a bit higher than the newer SCIMP boats. However, the trade off is that the preSCRIMP boats are considered not as well made and more prone to having issues...thou not always the case. Add to this the fact that newer is typically better due to advancements in production process, and I'd give the definite nod to SCRIPM boats when it comes to boats like J/44 vs. J/46. If the engineers in the group want to drill deeper, here's a link to a buyer's guild for J/105's, and they devote a chapter to discussing the SCRIMP process in far greater detail:
https://j105.org/j105-information/buyers-guide/#ar2b
Another rather minor inaccuracy that Bernie suggested was "running backs" on the J/44. They're actually more correctly known as "check stays", the difference being that they're not structure, but used to fine tune the rig in a variety of scenarios. For example we would crank them on a bit after a tack to put a bit more power in the main to accelerate out of the tack, then easy them off, or in a sea state upwind we'd wind them on a bit to keep the center of the mast from pumping. We also used check stays in a variety of J/Boats including J/35's, J/33's and many others. Day sailing or cruising the J/44 we'd disconnect the check stays and attach them up by the mast and out of the way....too much risk while casually sailing if someone forgetting to release the windward one in a gybe, esp., and taking the rig with it. Or, just take them out of the mast entirely if just cruising.
Al Goethe also has some good insights. However, be aware that J/Boats offered at least two cabin layouts for the J/44, three staterooms and one head, or two staterooms and two heads. The later had an enormous cockpit locker which simply devoured a LOT of gear and sails. Not sure where you'd store these without this locker. The other benefit is having an aft head just adjacent to the companionway is a big advantage for off shore access, a LOT less distance to travel each way. Meanwhile, the J/46's that I've seen have the two head, two stateroom layout, thou not necessarily all of them.
Finally, financial considerations. When the J/46 came out it was quite expensive, and even 3-4 yrs ago we watched one in our harbor still fetch over $350k. Currently there's one in Maine asking $225k, but just now see its "offer pending". J/44s on the other hand have pretty much bottomed out around $100k for a decent one, but bring at least that much to get it back to good nic to be comparable. The used market for them is pretty soft, but stable from my experience. I think the general consensus is that they're pretty long in the tooth and considerable on going maintenance will only get worse. Plus in terms of re-sale the "46 brings not only relative youth, but not-insignificant technical advancements throughout the boat, floating in a fully SCRIM build.
We recently sold our J/121, "allegro malvagio", ex-"Wicked", after four seasons, and last month purchased a J/42, "finezza veloce", ex-"Finesse", our eight J/Boat.
Fred deNapoli
Marblehead MA