skippi90, in all good faith I cannot recommend you buy that PSU, it could well be fine but on the other hand it could cause you problems. If you like living life on the edge and spending hours banging your head against the wall because your PC is freezing or rebooting then spend little money on the PSU.
If you like the easy life and really just want to get your machine built with the minimum of fuss and enjoy yourself then I can highly recommend you throw down more dollar for the PSU, it really is an important component and it will be powering your state of the art system.
I know money doesn't grow on trees but your putting together a real nice system there, get it right!
P.S: regarding that piece of **** case you bought, fair enough we all have different tastes in how we like things to look however the difference between building a system in a POS case compared to a proper thermally advantaged chassis are night and day. Apart from the actual building process which is a one off kinda a bad chassis will not give good airflow to your components and cause them to run hotter than they should.
Lol your pc is gonna be awesome when its built but it will look like something you buy at a computer fair for £250 all in!
[edit] happy to be proven wrong btw, you could mod it and make it awesome!