For the most part, Roland libraries load in okay except for a few things. The envelope settings are not converted whatsoever. Occasionally, the loop points are off slightly. You'll have to adjust the filter as well because Roland samplers apply an emphasis curve to the samples so you'll have to "de-emphasize" them to have them sound the same. In some cases, you may like the brighter sound of the samples themselves.
There may be software solutions out there that will read and convert these parameters but I'm not sure. Translator (by Rubber Chicken software at www.chickensys.com)
is a program that may do it now. The last time I checked, Translator would not convert the samples and patches over to EOS format but I do know that they were working on it.