I haven't followed kexec as close as some others but I believe it's still only running one core which seems to me like it would slow the phone down rather than speed it up. From what I do know about it is that it doesn't unlock the bootloader. It's able to hijack the kernel and run a custom kernel from boot. So while it will/should bring improvements to our phones I don't know how great those improvements will be.
I've never been one to flash different kernels (on unlocked devices) as I never seem to realize a noticeable difference. I quit overclocking my phones once I upgraded from the HTC Eris (absolutely required on that phone). I love the openness of unlocked phones in the fact that I can flash any radio to get better reception or different roms: MIUI, CM, AOSP, AOPK, Sense roms (most fully or almost fully functional), etc. I realize that most of these roms are available for Razr now but I haven't found a single non blur rom that consistently keeps data and mobile connection (big deal to me).
I love the build of Moto devices. They have less hardware issues, better battery, and better reception. Incorporate that with an unlocked bootloader....I'll make the jump when we get one on Verizon.
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