Identifying Lightmaps

I have the problem that some specific lighmaps looks pretty bad from the distance due to mipmaps. I found the lightmaps in the world settings. When I double click them I have the option to use no mipmaps. My first question. Is there any problem when using no mipmaps for lighmaps in general ? I have roughly 100 lightmaps in my scene. Is there any way to identify the lightmap that is used by a specific object ? Is it also somehow possible to tell lightmaps not to generate and use any mipmaps before I calculate lighting ? Any input is much appreciated.