It seems it only works when it wants to. Sometimes it'll dump it right, but most of the time it'll just give me nothing at all or unusable garbage. And don't get me started on trying to calculate the size (it doesn't help I've just been guessing so far).
Are you even placing 0x in front of the address/value? Otherwise it will consider what you typed as decimal.
Whoopsee. That's what I get for not being methodical.