USB boot is possible on RPi, but it's kind of a pain to get working as it is not compatible with every USB storage device.
Is this the case on the new Pis, or just on old ones? Every time I ask if the Pi foundation has got USB right on the newest Pi I get downmodded, even though they have fucked up USB again and again. The original Pi's USB craters under load and yes, compatibility is piss poor.
Do the new Raspberry Pis have working USB? Or is it unreliable shit just like the first Pis? Let's see how quick this comment gets downmodded by the Pi Police for asking really a quite important question.