They almost never keep their delivery time promise (google it for yourself).
On their website, it says (in Order Terms)
So by the time you get your hardware, 50 GH/s will be worthless.
You'll mine about 0.5 btc in total (as in, in a year although most will be mined in the first few months).
To answer your other question, you would just need a regular PC.
On their website, they have programs, drivers, etc and everything you need to start mining.