The blacklines most likely have Elpida IC's, but not the hypers. 99% chance they are gonna have BBSE IC's which are a little more sturdy, but won't hit the tight timings like Hypers. The Ridgebacks are most likely PSC IC's which are in all the over 2000mhz kits these days. Really for your expectations of 4ghz, you can't go wrong with either. Really I don't know which I would get in that case.