There is a CORRELATION between feeding from raised feedeers and bloat. Unfortunatly Linda Arndt feverishly disagrees and this seems to have created alot of controversy because most Dane owners agree thay they are good while many other giant breed owners pass by them these days. I do not use raised feeders. Period. While there is no conclusive evidence has been found it is hard to dispute that their is a very high correlation between the two. Many of the breeds that were in the purdue study were other breeds besides danes and many of these breeds are not typical raised feeders, but the increase in bloat did get higher when comparing, say weims, with raised feeds vs not.
I also think the argument that it is more comfortable for the dog is hog wash. My Saint Bernard and any of the fosters that lumber about the house have no more difficulty bringing their heads to the dish than my beagle, because physiologically they have the same basic structure and on a scale my beagles neck is no longer on his body than my 150lb Saints. If eating from the ground was such a trial for dogs don't we think that in the path of evolution a dog would present itself much differently to accomodate such a distressing position?
I most certainly look to other factors regarding bloat to predict if I have a dog in my care that may be more predisposed to it. Like SaraB said stress, genetics, many other strong facrtors are better predictors than a raised feeder. However in my home where a stressed foster, coming from unknown genetic heritage, often underweight...well I keep the raised feeders away becauase it is one of the factors that I CAN control.
It is a personal decision for each household. I have many clients that will ask me my opinion on it and I tell them why I don't use them but that doesn't mean my advice is the best for their dogs.