Two ferrets with second set of "needles"?  I don't understand....
 
Personally, I would have taken the first pair you found.  They obviously
need help.  Not everyone is up to rescuing and rehabilitating ferrets
though, so I can perfectly understand if you don't feel up to it.
 
No, ferrets don't all nip or bite.  That first pair is obviously biting
because they are unhappy with their lives.  It is nice that they get
free-roam time in the evening, but ferrets get up every 3-6 hours, and
need enough room to play - and food and water - at all times.  From the
sounds of it, I doubt they get enough human interaction time, and I
wouldn't be surprised if their food isn't even good ferret food.
 
Almost all ferrets, young or old, can and must be trained not to bite.
There is even hope for both of these pairs.  All they need is a little
patience and lots of love.  The FFD book tells you how to train them if
you decide to get one of these pairs - or if you settle on a kit.
 
Roger, Digger, Bear, Fox and Sniffles
[Posted in FML issue 3753]