Yes the altcoins are worth buying, the fact is that altcoins are with trading so now and than very profitable.
I think that you can make a lot of money with investing on altcoins.
It's worth buying that altcoin's , "but" There always a risk if that altcoin will going to rise up? Or to be dead soon the fact using or buying altcoin's were getting bitcoin to it making money to it ico's is are most profitable in internet.