I have a raspberry Pi, Beagle Bone Black and PcDuino.
Raspberry PI: don't like the fact that you have to boot off the sd card.
BBB - no complaints, nice board and has an optional display that's pretty nice
PcDuino - my favorite, more memory and flash than the other 2 devices and the v3s is in a really nice case.
The Pi and BBB lack a decent case (from what i can find)