I want to know what that someone has been smoking tbh.
The only part I'm remotely worried about is the HDD as I've never really used Hitachi's. They're supposedly very good today. I'd upgrade the CPU cooler sooner or later. It still is equal or even beats the H55. (lowest-end AIO watercooling setups, like the h55, are VERY bad)
For the HDD, I'd go for a WD Black. It's 88USD though, so you'll end up at about 742USD on using this one over the Hitachi.
As for the CPU Cooler, quite a few picks there but that's going to cost you considerably more. NH-D15 or 240/280MM AIO Watercooling setups require either a case with such mounting vents or be able to support the height of an NH-D15.
The NH-D15 runs for about 90USD, the better 240MM are at least 100USD and up.
Both the builds you posted have rather... less 'good' CPUs. A dualcore CPU for modern gaming is just no. It's good for casual gaming but if you want more performance and/or longevity, you're better off with a quadcore.
The AMD one is... well, AMD CPU. The top tier CPUs are Intel only. Mainly due to performance of when just one core is used from the 4.
Both builds only have 4GB of RAM. This is a flat out NO.
Either way, I've poked around yet again since I felt I could do better (forgot the max of 750USD ):