They're a fantastic little fish and I can't imagine not keeping them. They do notice drops in water quality and periods of stress tend to take their toll more than other similar fish (danio's etc) - I lost a few when moving house and trying to juggle setting up 4 tanks quickly - but if you keep on top of the water quality they're a great little fish and I can't stress this point enough: they colour up beautifully after a week or so at home. I've always kept them in well lit rooms and the colouration is fantastic.
One thing I've noticed with them is that they will school with just about anything - so far I've seen them school with pearl danio's, pentazona barbs, even peacock gobies - and not just when stressed or scared. It's probably fair to say they're my favourite schooling fish.
To summarise, if you can keep on top of the water changes to give them good quality water then get half a dozen or more. They're brilliant.