Nothing against anybody here, but factually some of the information is wrong. Most of the cable sets that come WITH any high quality power supply are usually thicker gauge and better quality than what normally comes with prebuilt sleeved cable sets or aftermarket sets. Not that there are not good quality aftermarket sleeved and non-sleeved sets out there, because there are, but you need to pay attention to what you are ordering because it's not a given.
Main point being when I hear somebody say that the cables that come with most power supplies, unless we are talking about cheap quality power supplies in which case getting cheap cables is a given since nobody is going to include quality cables with a cheap PSU, it's evident to me they really aren't familiar with the relevant aspects of high quality power supplies. There is also the additional fact that you REALLY need to be sure you are getting a set made specifically for the PSU in question since they are not all going to have the same pinouts at the PSU end of the cables. Also, it's a well known fact that many of these factory cables come with additional capacitors inline that further reduce ripple and noise and the vast majority of sleeved or aftermarket cables will lack those inline caps so hopefully it's a unit that already has mythical ripple and noise levels so that inline caps are not a necessity or even desirable benefit in the first place.
Many ways that not including the correct cables with the power supply could go wrong, but again, I don't really think it's a problem because I'm betting this is a product that will die a fairly rapid death on the market due to a lack of sales.