Hello,
I have a Netgear ReadyNAS Duo v2 with Debian installed directly on one of the HDDs and it is doing its job (data backup) just fine.
I got an offer for ReadyNAS Pro 2 (RNDP200U) Atom x2 1.8 GHz and upgradable up to 4 GB DDR3 RAM. Now I am searching for info if the unit can be re-installed with Debian/Ubuntu, but can't find anything.
The idea is to set the two drives as LVM partition and install Linux on it. It should run at least File Browser, Syncthing, Transmission and miniDLNA.