iPod mini - ALAC listening - Rockbox or native OS?

[hiss]

I'm going to repair/mod my 2nd gen iPod mini, so I was planning to use Rockbox until with further reading I found out that my iPod natively supports ALAC, which is the only format that I'm going to use.

Are there any advantages in running Rockbox anyway? Like better battery usage with ALAC, bug fixes that improve performance or something like that specific to the iPod nano?
I'm not going to be using any EQ and I'm going to use a lot of music with Japanese tags.

Any ideas and why I should prefer Rockbox?

Thank you.