This is just my personal experience, but when it comes to memory, I more look at the RMA, warranty, and just overall experience. The majority of ram really only comes from 3 top places, Samsung, Micron, and Hynix. You can individually research the ram chip model just to get an understanding of it, but for most people, when they are looking at ram, it's either to run @ stock speeds/timing or overclock (that's where the research comes in).
In regards to Kingston Hyper X, I'm currently running 3 of their products. Hyper X Predator 3200mhz ram, Hyper X Quad Cast Mic, and Hyper X full-sized mouse mat. Zero issues with any of them, all look and work great. I would buy hyper X again in a heartbeat. Mind you, I buy new, not used.