Ahhhhhh yes, you mean this one. Stupid me, my words "they can certainly do a hell of a lot more than that" obviously came across as meaning the exact opposite.You kind of proved yourself wrong with the rest of your post and saved me the trouble!! Thanks.
Crop = great for snap shots and posting online (although they can certainly do a hell of a lot more than that)
FF = Better low light handing, better dynamic range, wider field of view, full frame sensors are typically housed in more 'professional' bodies.
FF > Crop