Yes Next Gen (v3 seats) are arguably the best, preferentially over the Tesla Premiums (v4) but substantially over the original (v1 & v2). Unfortunately they are expensive to purchase and install as they are made to order, so you are looking at $5-$6k if you go through Tesla to buy them. If you get used seats elsewhere you just need to pay for the install, but definitely worth it. I have a friend who upgraded from Performance Seats (v1) to the Next Gens hes a very happy camper now.
I believe Tesla Abandoned the Next Gens because they as well as the ones beforehand were made by Recaro, and the new Tesla Premium seats were made by another company who Tesla Acquired thus its in-house.