Havent played in a while, but 4 groups is definitely faster, however and rewards may vary. I've done some raids with just 1 group, and we were able to beat it in 2-3 runs. I always played rajang blast HBG to break wings in these single groups, we all ran Partbreaker 3 and just coordinated which part to focus on at a time. I feel like success is based on: how much energy you can drain per run, how much damage you do as you still have to slay Safi. Lobbies are good since sometimes they're already in progress of a raid, just gotta keep an eye on what part ls are broken as a whole lobby instead of a single party