Why can't ASUS get their shit together with my board's BIOS?

I bought an Asus K8N-E Deluxe motherboard a couple of months ago, and while it generally works really well, it's been pissing me off with its memory settings. I have Corsair TWINX1024-3200C2PT memory, DDR400 memory with 2.5-3-3-6 latency. When my motherboard has the 1009 BIOS, I can set the DDR speed just fine to 400MHz, but even if I forcefully set the latency settings to 2.5-3-3-6, it forces me to use 3-3-3-7. What the hell? If I upgrade to the latest BIOS: 1010 or the beta 1010.3, I can set the latency settings to 2.5-3-3-6 just fine, but it forces me to run the memory speed at 333MHz. I can run the 1006 BIOS and set BOTH the memory speed to 400 MHz and the latency to 2.5-3-3-6, but then my system is unstable and randomly crashes.

I just can't fucking win. At this point I'm running with 1009, because even though I can't get the latency speed right, I'd rather run at 3-3-3-6 and 400 MHz than 2.5-3-3-6 and 333 MHz. Corsair's official response: It's a bug in the ASUS BIOS. I tend to trust them, as they have been nothing but awesome to me throughout two RMAs and even cross shipping my memory during a second RMA.

I just wish ASUS would get it right so I could have a reliable BIOS that both has the correct latency and correct memory speed. It's total bullshit that it can't even get the settings right when I forcefully override them in the BIOS settings.