Reduce clock speed for improved response time.
Reduce clock speed for improved response time.
In addition, latency will only slightly improve while MCLK/UCLK remain poor; your bandwidth will decline more significantly, leading to a greater negative effect on performance. Moreover, primary CL timing is minimal impact if your secondary components are correctly adjusted. If you're concerned about 6400/32 not functioning with EXPO, manually tuning it is fine—nothing to worry about. Provided you're prepared to invest time in manual DRAM adjustment.
When it's more affordable, there aren't many strong reasons to choose a pricier RAM kit that's slower, particularly because those MHz and timing values might actually swap positions. While you can't always tweak settings endlessly, you should usually have some flexibility in minor adjustments. That's why most users can manage things like lower CPU voltages without major issues.