If you check some of my recent posts I spent two non-consecutive weekends doing off roading in the Lake Arrowhead area. The problem with those roads is that they are not patrolled or kept clear during the winter so you are on your own. If you notice one of my photos is of a large tree that fell making the journey further not possible. On that specific trail, we came across another off roader on the way back and he mentioned the same thing. You drive a few miles and all is good, then fallen trees. This was due to a storm that occurred late last year. Hence I would still recommend taking the public roads. I know it's a pain from up there with all the turns but at least you'll avoid hassles. Unless you have a chainsaw on you ...