I went back to the Orca from the Beluga. Why?
- The Orca is much faster / has very strong thrusters, handles really well both in SC and normal space - particularly by acceleration and deceleration. Its insanely fast speed for its size (just like Im' Clipper) is ideal for passengers that don't want get scanned / high-G world landing / NPC escaping. The Beluga's thrusters are good, but not good enough for its size and surely not good enough for those speed-demanding tasks.
- The Orca is much lighter, since FD halved its hull mass in 2.3, it got not only further FSD jump range (now can easily past 30 Ly with mods which is pretty decent), but also more shield strength for self-defending. The Beluga can not even pack a shield generator that optimises its hull mass in it, which is a shame because it stands up really bad in a fight even with SLF onboard. As mentioned before, escaping is unlikely because of its slow speed, prepare to take hull or heat damage when you do so.
- The Orca is much cheaper than the Beluga, obviously. Since both ships do almost the same thing (not that many advantages transporting passengers in a Beluga honestly), the Orca has much more cost-performance ratio than the Beluga. Also you definitely don't want to loose your longtime trained NPC co-pilot in a Beluga by NPC attacking or crashing on a high-G world (it happened to me once).
The Beluga IMHO is just a double sized Orca (both outside and inside), but costs almost three times more than an Orca (both fully equipped). Not to mention it has serious heat issue because of its undersized power plant considering its thrusters (just like T-6, T-7 and T-9), and frustrating and confusing internal slots (no class 7 slot for a such large ship, are you kidding me FD?).
So I would not recommend the Beluga to any existing Orca pilots, unless you just want to fly the largest ship in the game.
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Sometimes I will need a class 6 luxury cabin for passenger missions (it happens), therefore I would recommend the Orca over the Dolphin if anyone has the money to invest building an Orca.