from one of the kernel devs:
Fidelizer ROMs have a lot of unworkable stuff under the hood. Unworked ALSA drivers, a lot of broken patches and tweaks, from Xperia smartphones, many settings from cyanogen mod, which are not applicable for X5-3 e.t.c.
You can trust me, because I completely disassembled his ROM and I know what is included in it. Unfortunately, most of these settings only harm the system and reduce the stability of the custom kernel.
We, with jkbuha tried to increase the stability of the kernel on this ROM, but we were not able to bring it to the required level.
In addition, the sound on this ROM is exactly the same as on the stock. I can guarantee it.
Unfortunately, I cannot recommend using it in conjunction with a custom kernel.
Stock Firmware + Custom Kernel is the way to go. And yes, there’s benchmark data (interpret from it what you will) showing better performance on CK across all builds (1416, 1704, & 2016 MHz).