I am using the 250 NAS I did have the pop ups with previous versions but not with 0710 b2 or b3.
The 250 has a usb port wich I have a 500 gb HD connected to. Has GB Ethernet but it doesn't seem to take advantage of it.
I have been using it with pluto / linuxmce for close to two years. (The pop ups occurred most frequently with 0704)
Other than the pop ups It has worked fine for me.
I need to clean up whats stored on it but thats another story.