There are a LOT of people at the hospital where I work who wear Crocs. I see quite a lot of them wearing the Beach model w/ the holes on top. I am not a nurse, but I wear Crocs almost every day. I used to have sore feet at the end of the day, but those days are GONE.
If I had my druthers, I would probably go for the Professional model. They are a little contoured, don't have holes in top but DO have them along the sides. They look very nice, in my opinion. I think DH will go over the edge if I buy one more pair though....I already have 5-6 pairs.
I do have a pair that is totally closed in....they did take some getting used to. I remember when I first wore them, I put them away for a LONG time before I wore them ever again. But then I got a 2nd wind and have been wearing them quite a bit this winter.
I think for the money, Crocs are a GREAT option for nursing staff. The nursing shoes are so darn expensive!