I made a full tests with I/O Schedulers to make everybody clear which one is better.
For me actually all is the same i think any of them perform prety good and there wouldnt be noticable inreal usage differience.
Kernel: [KERNEL] Kernel Sapec 2.1 TW_KK_Update 7_N9005
Rom: X-NOTE build 15.0
Benchmark used: AndroBench
CPU Max Freq 2.8ghz
Internal_storage read-ahead: 2048kB
ExternalSD read-ahead 2048kB
All tests were made 3 times and average score was taken.
IMG in dropbox: https://www.dropbox.com/s/isre15gs9hglvnm/Capture.PNG