I agree, they are fine by themselves also. If you have the room though go for the school. There aren't a lot of fish, besides damsels, that can be kept that way. Just get an odd number of them.
As with most schooling fish, the swim fast and far as their defense, not hide. So with that in mind, you need a 6' tank.
They are pretty hardy.
As XoXoX said, they will watch you as much as you watch them.