The E-Pro is the best value and provides the best support for future growth the USB 3.0 and SATA III. The i5 750 will do you well for a year or so depending on if you do heavy gaming. If you aren't a heavy gamer, you'll be set for years to come. If you are wanting a system to last for 3 to 4 years, your best bet is a LGA 1366 build, since they have the Hex-cores (6 cores) and as they prices come down, you can upgrade just the CPU and have plenty of horesepower. The i7 930 is a great value but at this point in time, you can't go wrong with the i5 750 (best bang for the buck CPU you can buy... IMO )
You will be happy with the ASUS P7P55D-E Pro, if you decide to make the purchase!!