@above: The dog grows into one of these:
http://www.chickensmoothie.com/archive/2008/September/ 4th litter on the page. Jealoussss, since one of those is my dream pet! Don't know about the rat, though.
And.. I just happen to be asking about how much closer this pet:

will get me to an X dog. Obviously the X dog is an '08 VR and this is only an '09, but I just would like to know a general value of it. Like, is the grinner next to nothing? Or is it a considerable amount to put in a trade for an X dog?