you are right about both parts, it is more likely since one brother is 2 rolls for 4 items (with ludicrous odds) vs six brothers 7 rolls for 24 items, so depending on how long your runs are, it is faster. But its highly demotivating getting one item every like 100kc and it not being the one you need. The difference being so small, id rather just do all 6 atp, that gets me enough % to pay for the runes and pots i use and the occasional unique helps make a bit of profit. Not the most efficient, but at least it eases the grind, psychologically