Honestly struggling to tell the difference between the two models. Not sure that $50 is worth the difference? I can't seem to get Swiftech's page to work, and it looks like they used the exact same images, I see no added stuff in the kit pictured.
Probably not worth it either way. I have the older H240-X and while it is a great product, it is expensive and kind of a hassle to build around. You have to be quite certain of clearance available in your case, since the reservoir and pump are bolted to the radiator, you also need to consider ease of access once it is installed.
If you are just using it as a CPU cooler, I suggest getting an off the shelf All-in-one like a Kraken X61 or the Corsair h110i or something similar.
If you intend to use it as a core of a custom loop: Most water cooling friendly cases are designed around 120mm class radiators. Usually leaning towards thicker 120, 240, 360, and even 480mm radiators. 120mm fans also produce greater static pressure.
In hindsight I would say discrete radiators, pumps/reservoirs is the way to go.