Kingston HyperX DDR3-1866 memory modules have only one disappointing drawback: extremely tall and unnecessary heat-spreaders that may cause some problems during system assembly. High price of this kit may also have a little discouraging effect on you, however, it is similar to what over overclocker memory kits run at these days. You can currently order a kit like that on Kingston’s web-site for $237. A memory kit with exact same specifications and features but with regular heat-spreaders - KHX14900D3K3/3GX – is selling for $219.
In my personal opinion, it would be a better buy, although it is hard to justify the almost 10 times higher price than that of regular DDR3-1067. Of course, overclocker memory that can work in a much broader frequency range, like Kingston HyperX DDR3-1866, offers overclockers much more flexibility. You will always be able to find the most optimal frequency and timings combination. But you have to decide if the result you will get in a few selected applications sensitive to memory frequency and timings is worth the investment.