Concealed is cheaper, it also offers more burst potential with the stun.The heal from swallow isn't that good in outnumbered situation because swallow is mostly used on offensive. When i'm on defensive(when i need the heal) i can't turn to use it (it gets blocked/roll dodged alot).
Swallow Soul is still better in 1v1 scenarios since it allows you (with siphoning attack and dark cloak)to always be on offensive and not having to worry about your HPs.
When outnumbered, the most annoying classes are Magsorc Magplar Stamplar. In duels i don't really struggle against any classes but stamina necromancer and stamblades are annoying to fight because they have good tools to counter magnb burst.
I also uploaded a 2vsX vidéo and you can see that my build changes alot in group since i need to be able to support and share the damage income with my mate(s).
Awesome video, my favorite part is reading the whispers from all the salty victims 👌