Concentrate on the chips. This will translate into clocks and timings. It doesn't matter what they are rated at, as long as they are capable of hitting the clocks you want with timings acceptable to your needs.
If you buy sticks that are rated as PC3700, but in fact these are made with chips that are actually overclocked DDR400 rated stuff, then you may not hit the 240+ that you are looking for since these sticks are already overclocked to begin with. The Infineon BE-5 would fall into this category. While these would hold tight timings, they will most likely require the use of dividers in orde to hit the 240+ clocks. I'm not saying not to do that, just be sure that you understand this going in.