No theyre not the ones rappers use, those are like $4000 microphones. These work perfect for home recording, especially just starting out. The MXL 990 is especially good for the price of it, its just real delicate. Make sure to keep it in its case when you're not using it and to keep it away from moisture (IE rooms that may leak when it rains). Of course you could not do this, it wouldn't necessarily destroy the mic - but you'll run a very high risk.
And no, they don't hiss. You need a mixer as well with these, because they require phantom power to operate. You can get a 2-channel Behringer mixer for about $60 as well which will due the job perfectly.