I've also used an A20 for compilation... briefly. And not much was compiled in the brief period ;)
As for the boot ROM blob, do you know if that is the 'boot0 and boot1' that Olimex apparently published the source code for?
I wonder if anyone's verified that the code in the boot room on this device really is what you get when you build the boot0 code? I wonder what sort of maliciousness you could fit in there if you tried...
no, the chances of them making a glaring and incompetent accidental mistake that compromises on security are far, far higher than them getting involved in deliberately adding malicious spying code into the device.
you have to remember that the A20 was designed along "unbrickable" lines, so that they could help out incompetent OEMs and ODMs who took it on themselves to "experiment" by making random changes to the design. any kind of DRM would be a serious impediment to that... so they didn't add any.