'Fancy' lights seem to often have a need to fasten directly to the ceiling, which is a pain as I do find loop-in type roses a nice east way to get the various wires in place.
Do similar junction boxes exist for use in the space above the ceiling? The MK et al ones in my various catalougues don't seem to have quite the right capacity. I tend to move the rose up there, but don't find it a very elegant solution.
IanC