embedded linux on MikroTik Routerboard RB800 ?

[legacy]

I am looking at MikroTik Routerboard RB800, that is a very interesting PowerPC-based micro-machine, but it's not clear to me *IF* it's possible to replace RouterOS (made by MikroTik, and installed in the built-in flash) with linux without having to pass through a sort of virtualization called "MetaRouter" (MicroTik technology and terminology, as far as I understand) 

I can't put a linux kernel inside a virtual machine running on the top of RouterOS because I need to access directly to the miniPCI mem-space and RouterOS doesn't allow a virtual machine to do so.

... anyone experienced with linux, running natively on RB800 or RB1000?

Thanks