User blog comment:Blackendedsoul/Unique Gomu Gomu/@comment-3181121-20120301091106/@comment-3425840-20120301103526

Bingo Panda, I actually wanted to talk about Chopper and Brook in the blog but did not do it cause it was getting too long.

Well Chopper's change is permanent, that much is true, but my point is not the out look but the ability bestowed upon the user as a result of eating the Devil Fruit. Since Chopper's ability is to transform which must take place by his own will and action and as Devil Fruit users are immobilized under the influence of Water, he does not fulfill the role, I mean someone can pull Luffy's head but definitely cannot make Chopper transform underwater (I am not sure about Kairoseki though, as Chopper has yet to face that predicament).

As for Brook: His case is too complicated and there are discussions going on all over the place about what really happens to him when he falls in the sea. Aside from that, his look is not a direct but an accidental effect of his Devil Fruit.

I am pretty sure that Kuma's ability is something that cannot be externally influenced like Luffy's and therefore his case is only the looks. If he is under effect of the standard Devil Fruit weaknesses, then his ability will be nullified and the only permanent mark he would have is solely the appearance.

However, I never thought about Alvida, she indeed is a person who would probably rival Luffy in this case, well I can except something when it is proven to me. Hats off to the great Panda for enlightening me (no sarcasm).