I do the 500ft above circuit height (remember that is 2000agl as circuit height is 1500 for quickies!) then descend to join crosswind when going to a strange airport or if I have any uncertainty about anything, it is always good IMO to get a good look at the strip from overhead to spot any hazards or at the very least to check the sock.
As for if it is safer than a downwind join, I have always thought that that time when in no mans land overhead and descending down to crosswind that that would have to be one of the most dangerous places around the field, after all there could be someone else doing the same thing at the same alt but could be going in any direction so it is definitely a place to keep a good lookout. But having said that I still think that is generally a safer option than a downwind join.
I still do downwind joins at times depending on a few things, if done correctly they are safe but keep an eye out for people doing 5mile wide circuits!