i was running 12 at the same time and they were all healthy and happy.
i guess it depends on how much time you have.
also,
the tamagotchi music star is fun...but it can get boring/annoying.
many people find it to be the 'worst version' because you have to buy your own food, and you'll have trouble if you're a street musician, which many people, including myself, have started off with on the first, second, or even third generation.
if you want to keep yourself entertained, i suggest you save up for a tama-iD.
it is definitely worth it.