Thanks to OMJ for the hard work. Sense 2.5 2012 | 6.5.5 | 23541 | v1.2 is really fast and stable!
However the pagepool changer bundled with the package doesn't seem to work. Maybe this tool worked for older ROMs, but it has never really worked since WM6.1. I followed an earlier WM6.1 thread (
http://forum.ppcgeeks.com/showthread.php?t=43110) to know that the actual pagepool is 24MB static in this ROM despite the tools says it's 20MB.
Here's what I did. Search a0 03 06 16 a0 13 00 10 83 e5 in RUU_signed.nbh and locate the following string:
18 16 a0 03 06 16 a0 13 00 10 83 e5 8b bb ff eb
According to the aforementioned thread, "18 16" means 24MB static pagepool. I change the first 2 bytes to "20 16" to make it 32MB:
20 16 a0 03 06 16 a0 13 00 10 83 e5 8b bb ff eb
Save and flash the ROM. Startup free memory reduced from 104.75MB to 97MB, by roughly 8MB (= 32MB - 24MB).
The pagepool changer also modifies 2 bytes, but at somewhere else. Since don't know exactly what the other 2 bytes do, I probably should set it back to the original "6MB"...