You did great for the price.
- Those video cards will be very close on your board and the one will get hotter... but should be OK
- I don't see any major issue with the case, probably OK for the price.
I don't care for recent reports regarding Samsung labor conditions (subsidiaries and such) and I've always found Western Digital to be the most reliable. Some of their NEWEST drives are quite fast:http://www.newegg.com/Product/Product.aspx?Item=N82E16822136533&cm_re=caviar_black_1tb-_-22-136-533-_-Product
That's all I have to say, pretty good build.